Wire breakage monitoring system

Abstract

To improve reliability by permitting surveillance of disconnection of wires including internal wires from a terminal block within a device to an electrical device in facilities in which the electrical device is connected to a host device.SOLUTION: In a disconnection surveillance system of facilities in which an electrical device 50 disposed in a terminal device 100 is connected to a host device 102, the electrical device 50 has a first normally closed switch SW1 and a second normally closed switch SW2, and a determination part 60 of the host device 102 determines non-operation and operation of the electrical device 50 and disconnection of a first wiring circuit and a second wiring circuit on the basis of a first wiring current i1 flowing to the first wiring circuit connected in a loop up to the host device 102 via the first normally closed switch SW1 and a first terminating resistor 36 from the host device 102, and a second wiring current i2 flowing to the second wiring circuit connected in a loop up to the host device 102 via the second normally closed switch SW2 and a second terminating resistor 38 from the host device 102.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a disconnection monitoring system for monitoring disconnection in a facility where electrical equipment is connected to a host device, such as tunnel emergency equipment where electrical equipment arranged on a fire hydrant device is connected to a disaster prevention receiving panel.

Background Art

[0002] Conventionally, fire hydrant devices are installed as tunnel emergency equipment in tunnels such as expressways and motorways. In the fire hydrant device, valves including a fire hose and a fire hydrant valve are stored in a fire hydrant storage compartment in a housing provided with a fire hydrant door, and for example, two fire extinguishers are stored in a fire extinguisher storage compartment in a housing provided with a fire extinguisher door. In addition, generally, fire hydrant devices are installed at predetermined intervals, for example, 50-meter intervals in the longitudinal direction of the tunnel.

[0003] In addition, as electrical equipment, the fire hydrant device is provided with a red indicator light, a transmitter (manual notification device), a pump start push button used by firefighters when starting a fire pump, a pump start interlocking device interlocked with the operation of the fire hydrant valve, a response lamp indicating that the transmitter has been pressed, and a telephone jack for making a call with a disaster prevention receiving panel installed in an electrical room during maintenance and the like.

[0004] Here, FIG. 20 is an explanatory diagram showing a part of wiring from the disaster prevention receiving panel to the electrical equipment arranged in the fire hydrant device. As shown in FIG. 20, among the electrical equipment in the fire hydrant device, a terminal block 30 arranged in the housing of the fire hydrant device is used for the transmitter 24, the pump start push button 32, the pump start interlocking device 34, the response lamp 26 and the telephone jack 28. The telephone line T, telephone common line TC, pump start line HA, manual notification line M, manual notification common line MC, response line MF, and response common line FC drawn out from the disaster prevention receiving panel and led into the housing of the fire hydrant device are connected. It should be noted that, for the red indicator light, a separate terminal block is used, so the description and illustration are omitted.

[0005] Of these electrical devices, the manual notification line M, pump start line HA, and manual notification common line MC, which are connected to the transmitter 24, pump start push button 32, and pump start interlocking device 34, which play a particularly important role in the event of a fire, are monitored for disconnection in the terminal block 30 by connecting a terminating resistor 46 between the terminals to which the manual notification line M and manual notification common line MC are connected, and by connecting a terminating resistor 48 between the terminals to which the pump start line HA and manual notification common line MC are connected. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2016-055073 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, conventional wire break monitoring does not detect wire breaks in the internal wiring from the terminal block 30 to the electrical equipment within the fire hydrant system, particularly the transmitter 24, the pump start push button 32, and the pump start interlocking device 34, which play a crucial role in the event of a fire. The state of the wire breaks remains unknown until they are first confirmed during functional verification tests conducted during periodic inspections of the emergency equipment, which means that the emergency equipment may not function properly in the event of a fire.

[0008] Furthermore, the breaks in the internal wiring are thought to be caused by the deterioration of the internal wiring cables and terminals of the terminal blocks over time, and although extremely rare, cases of such breaks have been found during past periodic inspections. In the case of emergency equipment in harsh environments such as tunnels, there is a need to further improve the reliability of the emergency equipment.

[0009] The present invention aims to provide a wire break monitoring system that improves reliability by enabling monitoring of wire breaks in wiring, including internal wiring from the terminal block inside the device to the electrical equipment, in equipment where electrical equipment is connected to a higher-level device, such as tunnel emergency equipment where electrical equipment located in a fire hydrant system is connected to a disaster prevention receiving panel. [Means for solving the problem]

[0010] (Wire breakage monitoring system) The present invention is a wire break monitoring system for equipment in which electrical equipment is connected to a higher-level device, The electrical equipment includes a first normally closed switch and a second normally closed switch that are opened in conjunction with a predetermined operation. The higher-level device is The first wiring current flows through the first wiring circuit, which is connected in a loop from the upper device through the first normally closed switch and the first terminator to the upper device, The second wiring current flows through the second wiring circuit, which is connected in a loop from the upper device through the second normally closed switch and the second terminator to the upper device, Based on, The system is characterized by determining whether an electrical device is inoperable, operational, open in the first wiring circuit, and open in the second wiring circuit.

[0011] (Wiring circuit configuration) Electrical equipment is placed in a terminal device equipped with a terminal block. The first wiring circuit consists of a first external signal line from the host device to the terminal block, a first internal wiring line from the terminal block to the terminal block via the first normally closed switch and the first terminator, and a first external common line from the terminal block to the host device. The second wiring circuit consists of a second external signal line from the higher-level device to the terminal block, a second internal wiring line from the terminal block to the terminal block via the second normally closed switch and the second terminator, and a second external common line from the terminal block to the higher-level device.

[0012] (Common external common line) The first external common line and the second external common line are designated as a common external common line.

[0013] (Internal wiring with a common connection for part of the external common line) A portion of the first internal wiring from the first normally closed switch on the common external common line side to the terminal block and a portion of the second internal wiring from the second normally closed switch on the common external common line side to the terminal block are made common, and the terminal block is connected by the common internal wiring.

[0014] (Disconnection detection 1) The higher-level device is If the first wiring current and the second wiring current are detected, it is determined that the electrical equipment is not operating. If neither the first wiring current nor the second wiring current is detected, it is determined that the electrical equipment is operating. If the first wiring current is not detected but the second wiring current is detected, it is determined that the first wiring circuit is open. If the first wiring current is detected and the second wiring current is not detected, it is determined that the second wiring circuit is open.

[0015] (Disconnection detection 2) The higher-level device is If the first wiring current and the second wiring current are detected, it is determined that the electrical equipment is not operating. If the first wiring current is not detected but the second wiring current is detected, it is determined that the first wiring circuit is open. If the first wiring current is detected and the second wiring current is not detected, it is determined that the second wiring circuit is open. If the first and second wiring currents are not detected, a determination is further made based on the third wiring current flowing through the third wiring circuit, which is connected in a loop from the higher-level device to the higher-level device via the first external signal line, the first internal wiring, the second internal wiring, and the second external signal line. If a current is detected in the third wiring, it is determined that the external common wire is broken. If no current is detected in the third wiring, it is determined that the electrical equipment is operating.

[0016] (Monitoring for disconnections in wiring circuits where multiple electrical devices are connected in stages) There are multiple electrical components, The first wiring circuit is connected in a loop from the host device to the host device via the first normally closed switch and the first terminator of all electrical equipment, The second wiring circuit is connected in a loop from the host device to the host device via the second normally closed switch and the second terminator of all electrical equipment.

[0017] (Disconnection monitoring for wiring circuits with a plurality of individually connected electrical equipment) There are a plurality of electrical equipment, The first terminator and the second terminator are provided for each electrical equipment, A plurality of first wiring circuits are formed, for each electrical equipment, by connecting in a loop from the host device to the host device via the first normally closed switch and the first terminator of the electrical equipment, A plurality of second wiring circuits are formed, for each electrical equipment, by connecting in a loop from the host device to the host device via the second normally closed switch and the second terminator of the electrical equipment, The host device determines non-actuation of each electrical equipment, actuation of each electrical equipment, disconnection of each first wiring circuit, and disconnection of each second wiring circuit based on the first wiring current flowing in the first wiring circuit for each electrical equipment and the second wiring current flowing in the second wiring circuit for each electrical equipment.

[0018] (Disconnection monitoring when a plurality of wiring circuits with a plurality of electrical equipment connected stepwise are provided) The electrical equipment are divided into predetermined groups and exist in plurality, The first terminator and the second terminator are provided for each predetermined group, A plurality of first wiring circuits are formed, for each predetermined group, by connecting in a loop from the host device to the host device via all the first normally closed switches and the first terminator of the electrical equipment belonging to the predetermined group, A plurality of second wiring circuits are formed, for each predetermined group, by connecting in a loop from the host device to the host device via all the second normally closed switches and the second terminator of the electrical equipment belonging to the predetermined group, The host device determines non-actuation of the electrical equipment belonging to each group, actuation of the electrical equipment belonging to each group, disconnection of each first wiring circuit, and disconnection of each second wiring circuit based on the first wiring current flowing in the first wiring circuit for each predetermined group and the second wiring current flowing in the second wiring circuit for each predetermined group.

[0019] (Tunnel emergency equipment) The equipment targeted by the wire break monitoring system is emergency equipment for tunnels in which electrical equipment located on a fire hydrant system or manual notification device is connected to a disaster prevention receiving panel that functions as a higher-level device. The electrical equipment includes a transmitter, a pump starter button, and a pump starter interlocking device. [Effects of the Invention]

[0020] (Effectiveness of the wire breakage monitoring system) According to the wire break monitoring system of the present invention, electrical equipment equipped with a first normally closed switch and a second normally closed switch that are opened in conjunction with a predetermined operation is connected to a higher-level device. A first wiring circuit is formed in a loop from the higher-level device via the first normally closed switch and a first terminator to the higher-level device, and a second wiring circuit is formed in a loop from the higher-level device via the second normally closed switch and a second terminator to the higher-level device. The higher-level device can determine whether the electrical equipment is inoperable, operational, or if the first wiring circuit is broken, and whether the second wiring circuit is broken, based on the first wiring current flowing through the first wiring circuit and the second wiring current flowing through the second wiring circuit. With this system, it is possible to monitor the first and second wiring circuits, including the internal wiring from the terminal block to the electrical equipment, which could not be monitored in conventional tunnel emergency equipment to which the wire break monitoring system is applied. Even if a wire break occurs in the internal wiring due to aging or other reasons, the break can be detected, enabling prompt repair and restoration. Furthermore, even in harsh environments like tunnels, where high reliability is required for emergency equipment, the system can monitor for disconnections, including internal wiring, ensuring a sufficiently high level of reliability.

[0021] Furthermore, by using a first normally closed switch and a second normally closed switch that are interlocked, that is, a switch with two interlocking normally closed contacts (a two-circuit b-contact switch), current flows through the first and second wiring circuits when the electrical equipment is not in operation, i.e., when the equipment is in normal operation, making it easy to perform open circuit monitoring based on current.

[0022] Furthermore, when electrical equipment is activated, the normally closed switch is opened, resulting in the same state as a disconnection in both the first and second wiring circuits. However, by using the interconnected first and second normally closed switches, it is possible to distinguish between the activation of electrical equipment and a disconnection in either the first or second wiring circuit. This allows for display and control in accordance with the determination result, indicating whether electrical equipment has been activated or a disconnection has occurred.

[0023] (Effect of common external wires) When electrical equipment is arranged on a terminal device equipped with a terminal block, and the first and second wiring circuits consist of an external signal line from the higher-level device to the terminal block, internal wiring from the terminal block to the terminal block via corresponding normally closed switches and terminators, and an external common line from the terminal block to the higher-level device, the number of wires from the higher-level device to the terminal block of the terminal device can be reduced by making the external common line of the first and second wiring circuits common, thereby reducing equipment costs.

[0024] (Effect of using a common internal wiring system for a portion of the external common wire) Furthermore, by making a portion of the first internal wiring from the first normally closed switch on the common external common line side to the terminal block and a portion of the second internal wiring from the second normally closed switch on the common external common line side to the terminal block common, and connecting to the terminal block with the common internal wiring, the number of terminals required for the terminal block can be reduced, allowing the use of a terminal block with fewer terminals and thus reducing equipment costs.

[0025] (Effect of wire break detection 2) If the external common wire is shared between the first and second wiring circuits and breaks, the first wiring current of the first wiring circuit and the second wiring current of the second wiring circuit will not be detected, making it impossible to distinguish between a break in the external common wire and the operation of electrical equipment based on the first and second wiring currents alone. However, if the first and second wiring currents are not detected, a determination can be made based on the third wiring current flowing through a third wiring circuit that is connected in a loop from the higher-level device via the first external signal line, first internal wiring, second internal wiring, and second external signal line to the higher-level device. This allows for a distinction between a break in the external common wire and the operation of electrical equipment. This reduces equipment costs without increasing the number of external common wires and eliminates the need for on-site verification by workers. [Brief explanation of the drawing]

[0026] [Figure 1] This is an explanatory diagram showing an overview of tunnel emergency equipment. [Figure 2] This is an explanatory diagram showing a fire hydrant system. [Figure 3] This wiring diagram shows a first embodiment of a wire break monitoring system, as an example of a system in which a single electrical device located on a single terminal device is connected to a higher-level device. [Figure 4] This is an explanatory diagram showing the determination content by the determination unit installed in the higher-level device shown in Figure 3. [Figure 5] This is an explanatory diagram showing another embodiment in which the external common lines of the first embodiment are separated into a first external signal line and a second external signal line. [Figure 6] This is an explanatory diagram showing another embodiment of the determination unit in the first embodiment that determines whether an electrical device is operating or an external common wire is broken. [Figure 7] Figure 6 is an explanatory diagram showing the determination process performed by the determination unit. [Figure 8] This wiring diagram shows a second embodiment of a wire breakage monitoring system, using as an example a system in which electrical equipment, with one unit placed on each of multiple terminal devices, is connected in stages to a higher-level device. [Figure 9]This is an explanatory diagram showing another embodiment in which the external common lines of the second embodiment are separated into a first external signal line and a second external signal line. [Figure 10] This wiring diagram shows a third embodiment of a wire break monitoring system, as an example of a system in which multiple electrical devices located on a single terminal device are connected to a higher-level device. [Figure 11] Figure 10 is an explanatory diagram showing the structure of the terminal block that is placed on the terminal device. [Figure 12] This is an explanatory diagram showing another embodiment in which the external common lines of the third embodiment are separated into a first external signal line and a second external signal line. [Figure 13] This wiring diagram shows a fourth embodiment of a wire breakage monitoring system, as an example of a system in which electrical equipment is connected in stages to multiple terminal devices that are arranged on a higher-level device. [Figure 14] This is an explanatory diagram showing another embodiment in which the external common lines of the fourth embodiment are separated into a first external signal line and a second external signal line. [Figure 15] This is an explanatory diagram showing an embodiment different from Figure 14, in which the external common lines of the fourth embodiment are separated into the first external signal line and the second external signal line. [Figure 16] This is a wiring diagram showing the first stage fire hydrant device of the tunnel emergency equipment shown in Figure 1, to which the fourth embodiment of the wire break monitoring system is applied. [Figure 17] This is a wiring diagram showing the final stage of the tunnel emergency equipment shown in Figure 1, to which the fourth embodiment of the wire break monitoring system is applied. [Figure 18] Figure 16 shows the wiring diagram for the first stage of the fire hydrant system, and Figure 17 shows the wiring circuits for the transmitter, pump start push button, and pump start interlocking device. [Figure 19] Figure 18 is an explanatory diagram showing the switching of the voltage polarity of the terminals of the disaster prevention receiver panel according to another embodiment of the determination unit that determines whether the electrical equipment is operating or the external common wire is broken. [Figure 20] This is a wiring diagram showing the wiring for some of the electrical equipment in a conventional fire hydrant system. [Modes for carrying out the invention]

[0027] The following describes in detail an embodiment of the wire breakage monitoring system according to the present invention, based on the drawings. However, the present invention is not limited to the following embodiments.

[0028] [Basic Concepts of the Embodiment] First, the basic concepts of the embodiment will be explained. The embodiment is a wire break monitoring system that monitors wire breaks in equipment to which electrical equipment is connected to a higher-level device. More specifically, it relates to a wire break monitoring system that monitors wire breaks in tunnel emergency equipment to which electrical equipment, including a transmitter, pump start push button, and pump start interlocking device located in a fire hydrant system, is connected to a disaster prevention receiving panel that functions as a higher-level device.

[0029] Here, "higher-level device" refers to a device that primarily manages or controls lower-level devices connected to it, and lower-level devices are primarily managed or controlled devices or controlled devices managed or controlled by the higher-level device. Lower-level devices include various "terminal devices" such as fire hydrant systems in tunnel emergency equipment, and include (transmitters and other) equipment, as well as electrical equipment, electrical components, etc., installed in or attached to these devices.

[0030] Furthermore, "electrical equipment" includes equipment, devices, components, etc., that are connected in a manner that can be managed or controlled by a higher-level device, and comprises a first normally closed switch and a second normally closed switch that are opened in conjunction with a predetermined operation.

[0031] Furthermore, as a disconnection monitoring system for equipment connected to a higher-level device using electrical components, it can be divided into the following four embodiments.

[0032] The first embodiment of the wire break monitoring system targets equipment in which electrical equipment is connected to a higher-level device. The electrical equipment includes a first normally closed switch and a second normally closed switch that are opened in conjunction with a predetermined operation. The higher-level device determines whether the electrical equipment is inoperable, operational, open in the first wiring circuit, or open in the second wiring circuit based on a first wiring current flowing through a first wiring circuit that is connected in a loop from the higher-level device via the first normally closed switch and a first terminator, and a second wiring current flowing through a second wiring circuit that is connected in a loop from the higher-level device via the second normally closed switch and a second terminator. Here, "wiring current" refers to the current flowing through the wiring circuit via each normally closed switch of the electrical equipment.

[0033] Furthermore, as a more specific example of a wiring circuit, the electrical equipment may be arranged on a terminal device equipped with a terminal block, and the first wiring circuit may consist of a first external signal line from the higher-level device to the terminal block, a first internal wiring line from the terminal block to the terminal block via a first normally closed switch and a first terminator, and a first external common line from the terminal block to the higher-level device, and the second wiring circuit may consist of a second external signal line from the higher-level device to the terminal block, a second internal wiring line from the terminal block to the terminal block via a second normally closed switch and a second terminator, and a second external common line from the terminal block to the higher-level device.

[0034] Furthermore, a "terminal block" is a device that relays connections when electrical equipment is connected in a way that allows it to be managed or controlled by a higher-level device. "Internal wiring" refers to the wiring that connects electrical equipment located on the same terminal device to the terminal block, and includes internal signal lines, internal common lines, etc. In contrast, "external signal wiring" and "external common lines" refer to wiring that does not fall under internal wiring, such as wiring that connects the higher-level device to the terminal block of the terminal device, and are included in "external wiring".

[0035] Alternatively, the first external common wire and the second external common wire may be made a common external common wire, and a portion of the first internal wiring from the first normally closed switch on the common external common wire side to the terminal block and a portion of the second internal wiring from the second normally closed switch on the common external common wire side to the terminal block may be made common, and the terminal block may be connected by the common internal wiring.

[0036] Furthermore, as a more specific determination of a broken wire, the higher-level device may determine that the electrical equipment is not operating if both the first and second wiring currents are detected, determine that the electrical equipment is operating if neither the first nor the second wiring currents are detected, determine that the first wiring circuit is broken if the first wiring current is not detected but the second wiring current is detected, and determine that the second wiring circuit is broken if the first wiring current is detected but the second wiring current is not detected.

[0037] Furthermore, as a more specific method for determining a broken wire, the higher-level device may determine that the electrical equipment is not operating if both the first and second wiring currents are detected; determine that the first wiring circuit is broken if the first wiring current is not detected but the second wiring current is detected; determine that the second wiring circuit is broken if the first wiring current is detected but the second wiring current is not detected; determine that the electrical equipment is operating if neither the first nor the second wiring currents are detected; and if neither the first nor the second wiring currents are detected, the higher-level device may further make a determination based on the third wiring current flowing through a third wiring circuit that is connected in a loop from the higher-level device via the first external signal line, the first internal wiring, the second internal wiring, and the second external signal line to the higher-level device. If the third wiring current is detected, the higher-level device may determine that the external common wire is broken; and determine that the electrical equipment is operating if the third wiring current is not detected.

[0038] The second embodiment of the wire break monitoring system is for equipment in which multiple electrical devices are connected to a higher-level device by a single first wiring circuit and a second wiring circuit. The first wiring circuit is connected in a loop from the higher-level device to the higher-level device via the first normally closed switches and first terminators of all the electrical devices. The second wiring circuit is also connected in a loop from the higher-level device to the higher-level device via the second normally closed switches and second terminators of all the electrical devices. The higher-level device determines whether an electrical device is inoperable, operating, a wire break in the first wiring circuit, or a wire break in the second wiring circuit based on the first wiring current flowing through the first wiring circuit (connected in a loop from the higher-level device to the higher-level device via the first normally closed switches and first terminator) and the second wiring current flowing through the second wiring circuit (connected in a loop from the higher-level device to the higher-level device via the second normally closed switches and second terminator).

[0039] The third embodiment of the wire break monitoring system is for equipment in which multiple electrical devices are connected to a higher-level device by individual first and second wiring circuits. Multiple first wiring circuits are formed for each electrical device by connecting in a loop from the higher-level device to the higher-level device via the electrical device's first normally closed switch and first terminator. Multiple second wiring circuits are formed for each electrical device by connecting in a loop from the higher-level device to the higher-level device via the electrical device's second normally closed switch and second terminator. The higher-level device determines whether each electrical device is inoperable, operational, open in each first wiring circuit, or open in each second wiring circuit based on the first wiring current flowing through the first wiring circuit and the second wiring current flowing through the second wiring circuit for each electrical device.

[0040] The fourth embodiment of the wire break monitoring system is an embodiment that combines the second embodiment of the wire break monitoring system and the third embodiment of the wire break monitoring system, and targets equipment in which a plurality of electrical devices are provided for each predetermined group relative to a higher-level device and connected by individual first wiring circuits and second wiring circuits for each predetermined group. Multiple first wiring circuits are formed for each predetermined group by connecting in a loop from the higher-level device to the higher-level device via all first normally closed switches and first terminators of the electrical devices belonging to the predetermined group, and multiple second wiring circuits are formed for each predetermined group by connecting in a loop from the higher-level device to the higher-level device via all second normally closed switches and second terminators of the electrical devices belonging to the predetermined group, and the higher-level device determines non-operation of electrical devices belonging to each group, operation of electrical devices belonging to each group, wire breaks in each first wiring circuit, and wire breaks in each second wiring circuit based on the first wiring current flowing through the first wiring circuit and the second wiring current flowing through the second wiring circuit for each predetermined group.

[0041] The following describes specific embodiments. In the specific embodiments shown below, first, an overview of a tunnel emergency system is described in which the electrical equipment of a fire hydrant system, which functions as a terminal device, is connected to a disaster prevention receiving panel, which functions as a higher-level device to which the wire break monitoring system is applied. Next, first to fourth embodiments of the wire break monitoring system for a system in which predetermined electrical equipment located at the terminal device is connected to the higher-level device are described. Finally, a specific embodiment of a tunnel emergency system to which the wire break monitoring system is applied is described.

[0042] [Specific details of the embodiment] We will now provide a more detailed explanation of the wire break monitoring system and tunnel emergency equipment. The details will be divided as follows: a. Overview of tunnel emergency equipment b. First embodiment of the wire breakage monitoring system b1. Host system and terminal system b2. Judgment part b3. Other embodiments of the determination unit c. Second embodiment of the wire breakage monitoring system d. Third embodiment of the wire breakage monitoring system e. Fourth embodiment of the wire breakage monitoring system f. Specific embodiment of tunnel emergency equipment to which a wire break monitoring system is applied f1. Wiring circuit for the first stage fire hydrant system f2. Wiring circuit for the final stage fire hydrant system f3. Wiring circuits monitored for disconnection g. Modified form of the present invention

[0043] [a. Overview of tunnel emergency equipment] The outline of the tunnel emergency equipment to which the wire break monitoring system of this embodiment is applied will be described in more detail below.

[0044] As shown in Figure 1, the tunnel emergency equipment consists of wiring cables 14 from a disaster prevention receiving panel 12 installed in the tunnel facility's electrical room, which are connected in stages to, for example, four fire hydrant devices 10(10-1) to 10(10-4) installed in each longitudinal unit section of the tunnel. The disaster prevention receiving panel 12 is equipped with a judgment unit 60 that monitors the operation of the electrical equipment installed in the fire hydrant devices 10(10-1) to 10(10-4) and the disconnection of the wiring cables 14.

[0045] Here, "connected in stages" means that the electrical equipment is connected sequentially from the highest-level equipment to the final-level equipment, starting from the disaster prevention receiving panel to the first-stage fire hydrant device, then from the first-stage electrical equipment to the next-stage electrical equipment, and so on. Of the fire hydrant devices 10(10-1) to 10(10-4), the fire hydrant device 10(10-1) that is connected to the disaster prevention receiving panel 12 in terms of wiring connections is the "first stage," and the fire hydrant device 10(10-4) that is connected to the furthest position is the "final stage." Furthermore, for example, from the perspective of fire hydrant device 10(10-2), fire hydrant device 10(10-1) is the "preceding stage," and fire hydrant device 10(10-3) is the "next stage." Thus, the fire hydrant device located one stage further down from itself is the "next stage" fire hydrant device, and the fire hydrant device located one stage further down from itself is the "preceding stage" fire hydrant device. The same applies when the "disaster prevention receiving panel" is the "higher-level device" and the "fire hydrant device" is the "terminal device."

[0046] Furthermore, the wiring cable 14 includes high-voltage wiring cables for commercial AC power and low-voltage wiring cables for a predetermined DC voltage power supply. Low-voltage wiring cables include, for example, those composed of one or more signal lines and a common line.

[0047] Next, the fire hydrant device 10(10-1) will be described in detail. The same applies to the fire hydrant devices 10(10-2) to (10-4). The fire hydrant device 10(10-1), as shown in Figure 2 for example, has a structure divided into a housing 10a which houses the fire hydrant and a housing 10b which houses the fire extinguisher, and decorative frames 11a and 11b are attached to the front of the housings 10a and 10b.

[0048] The door opening of the decorative frame 11a of the housing 10a is divided into upper and lower sections. A forward-tilting fire hydrant door 15 that opens downward on a hinge is installed on the lower side of the door opening, and a maintenance door 16 that opens upward on a hinge is installed on the upper side of the door opening. Inside this maintenance door, which is the fire hydrant storage section, are stored fire hoses and valves including fire hydrant valves.

[0049] On the left side of the door opening of the decorative frame 11b of the housing 10b, a fire extinguisher door 18 is provided, which opens horizontally to the left by a hinge, and the fire extinguisher storage area inside can accommodate, for example, two fire extinguishers. In addition, a viewing window is provided on the lower side of the fire extinguisher door 18, allowing the presence or absence of fire extinguishers to be checked from the outside.

[0050] An electrical access door 20 is provided on the right side of the door opening of the decorative frame 11b, which opens horizontally to the right by a hinge. The electrical access door 20 is equipped with electrical equipment such as a red indicator light 22, a transmitter 24, and a response lamp 26, and a telephone jack is provided inside the housing 10b of the electrical access door 20.

[0051] The red indicator light 22 is always lit so that the location of the fire hydrant device 10 (10-1) can be seen from a distance. In the event of a fire, when the transmitter 24 is pressed and the switch on the transmitter 24 is activated, a transmission signal is sent to the fire prevention receiving panel in the electrical room, and a fire alarm is output. In response, a response signal is sent from the fire prevention receiving panel, the red indicator light 22 flashes, and the response lamp 26 lights up.

[0052] The right side of the housing 10a houses the valves, and a water supply pipe drawn in from the outside is connected to a fire hose via a water tap, a fire hydrant valve, and an automatic pressure regulating valve. The fire hydrant valve is opened and closed by a fire hydrant valve opening / closing lever, and opening or closing the fire hydrant valve opening / closing lever turns the switch of the pump activation interlocking device 34 on or off. In addition, a pump activation push button 32 used by the fire brigade is provided inside when the maintenance door 16 is opened. Alternatively, the pump activation push button 32 may be provided inside when the fire hydrant door 15 is opened.

[0053] Behind the fire extinguisher door 18, on the interior rear of the housing 10b, are terminal boxes 25a and 25b equipped with terminal blocks. The terminal block of terminal box 25a is connected to the high-voltage wiring cable (external wiring) from the disaster prevention receiving panel, as well as to the internal wiring for the red indicator light 22.

[0054] Furthermore, the terminal block of terminal box 25b is connected to the low-voltage wiring cable (external wiring) from the disaster prevention receiving panel, as well as to the internal wiring for the transmitter 24, response lamp 26, telephone jack, pump start push button 32, and pump start interlocking device 34. Here, the wiring connecting the disaster prevention receiving panel to the electrical equipment of the fire hydrant system is divided into "external wiring" on the disaster prevention receiving panel side and "internal wiring" on the electrical equipment side, with the terminal block as the dividing line.

[0055] [b. First embodiment of the wire breakage monitoring system] Here, the first embodiment of the wire breakage monitoring system will be described in more detail, using as an example a system in which a single electrical device located on a single terminal device is connected to a higher-level device. Figure 3(A) shows an example of a wiring circuit diagram of the wire breakage monitoring system, and Figure 3(B) shows a schematic of the wiring to the terminals of the terminal block. Furthermore, this explanation assumes that the wiring is connected to a switch provided on the electrical device.

[0056] (b1. Host device and terminal device) As shown in Figure 3(A), for example, a first external signal line 104, a second external signal line 106, and an external common line 108 are drawn out from the host device 102 as external wiring to the terminal device 100. In this embodiment, a first wiring circuit including the first external signal line 104 and the external common line 108, and a second wiring circuit including the second external signal line 106 and the external common line 108 are configured. Here, the connection terminals for the first external signal line 104, the second external signal line 106, and the external common line 108 in the host device 102 are designated as terminals A, B, and C, respectively.

[0057] The terminal device 100 is equipped with electrical equipment 50 and a terminal block 30. The electrical equipment 50 is equipped with a first normally closed switch SW1 and a second normally closed switch SW2. The first normally closed switch SW1 and the second normally closed switch SW2 are two-circuit switches that operate in conjunction with a predetermined operation, such as a push-button operation. They are closed when not in operation (off) and open when operated (on), and maintain the open state until operated again. They are alternate-type switches and are known as "two-circuit normally closed contact switches".

[0058] The first normally closed switch SW1 and the second normally closed switch SW2 of the electrical equipment 50 are connected via terminal block 30 to the first external signal line 104, the second external signal line 106, and the external common line 108 from the higher-level device 102 by internal wiring. Terminals A1 to A8 are assigned to the terminal block 30 to form the first and second wiring circuits.

[0059] First, in the first wiring circuit, the first external signal line 104 from terminal A of the host device 102 is connected to terminal A1 of the terminal block 30, the external common line 108 from terminal C of the host device 102 is connected to terminal A7 of the terminal block 30, the first internal wiring to one terminal of the first normally closed switch SW1 is connected to terminal A2 of the terminal block 30, the first internal wiring from the other terminal of the first normally closed switch SW1 is connected to terminal A8 of the terminal block 30, terminals A1 and A2 of the terminal block 30 are connected via a first termination resistor 36 which functions as a terminator, and terminals A7 and A8 of the terminal block are connected, thereby forming a loop line via the first normally closed switch SW1 and the first termination resistor 36.

[0060] Therefore, when a predetermined power supply voltage (wiring voltage) is applied from the upper-level device 102 between the external first signal line 104 and the external common line 108, the first wiring current i1, determined by the resistance value of the first termination resistor 36, flows through the first normally closed switch SW1 into the first wiring circuit.

[0061] Next, in the second wiring circuit, the second external signal line 106 from terminal B of the host device 102 is connected to terminal A3 of the terminal block 30, the external common line 108 from terminal C of the host device 102 is connected to terminal A5 of the terminal block 30 via terminal A7, the second internal wiring to one terminal of the second normally closed switch SW2 is connected to terminal A4 of the terminal block, the second internal wiring from the other terminal of the second normally closed switch SW2 is connected to terminal A6 of the terminal block 30, terminals A3 and A4 of the terminal block 30 are connected via a second termination resistor 38 which functions as a terminator, and terminals A5 and A6 of the terminal block are connected, thereby forming a loop line via the second normally closed switch SW2 and the second termination resistor 38.

[0062] Therefore, when a predetermined power supply voltage (wiring voltage) is applied from the upper-level device 102 between the second external signal line 106 and the external common line 108, the second wiring current i2, determined by the resistance value of the second termination resistor 38, flows through the second wiring circuit via the second normally closed switch SW2. Although the resistance values ​​of the first termination resistor 36 and the second termination resistor 38 are arbitrary, in this embodiment, the first wiring current i1 and the second wiring current i2 are set to the same value by setting the first termination resistor 36 and the second termination resistor 38 to the same resistance value.

[0063] Here, the path of the first wiring circuit that forms a loop line passing through the first normally closed switch SW1 and the first termination resistor 36 is indicated by symbols as follows: [Terminal A of the host device 102]-[First external signal line 104]-[Terminal A1 of the terminal block 30]-[First termination resistor 36]-[Terminal A2 of the terminal block 30]-[First internal wiring]-[First normally closed switch SW1]-[First internal wiring]-[Terminal A8 of the terminal block 30]-[Terminal A7 of the terminal block 30]-[External common line 108]-[Terminal C of the host device 102].

[0064] Furthermore, the path of the second wiring circuit that forms a loop line passing through the second normally closed switch SW2 and the second termination resistor 38 is indicated by symbols as follows: [Terminal B of the host device 102]-[Second external signal line 106]-[Terminal A3 of the terminal block 30]-[Second termination resistor 38]-[Terminal A4 of the terminal block 30]-[Second internal wiring]-[Second normally closed switch SW2]-[Second internal wiring]-[Terminal A6 of the terminal block 30]-[Terminal A5 of the terminal block 30]-[Terminal A7 of the terminal block 30]-[External common line 108]-[Terminal C of the host device 102].

[0065] The terminals A1 to A8 of the terminal block 30 shown in Figure 3(A) are arranged in a row, for example, as shown in the structure of the terminal block 30 in Figure 3(B). In Figure 3(B), the right side of the terminal block 30 is the external wiring for the higher-level device 102, and the left side is the internal wiring for the electrical equipment 50. As mentioned above, the first termination resistor 36 is connected between terminals A1 and A2 of the terminal block 30, and the second termination resistor 38 is connected between terminals A3 and A4. The connection positions of the first termination resistor 36 and the second termination resistor 38 can be any position on each loop line. For example, the first termination resistor 36 may be connected between terminals A7 and A8 of the terminal block 30, and the second termination resistor 38 may be connected between terminals A5 and A6.

[0066] (b2. Judgment part) The determination unit 60 of the higher-level device 102 performs a determination process based on the first wiring current i1 of the first wiring circuit and the second wiring current i2 of the second wiring circuit, for example, as shown in the table in Figure 4.

[0067] First, in the normal state when the electrical equipment is not operating, the first normally closed switch SW1 and the second normally closed switch SW2 are closed, and if there are no open circuits in the first and second wiring circuits, the first wiring current i1 and the second wiring current i2 flow normally. For this reason, the determination unit 60 of the higher-level device 102 detects the first wiring current i1 and the second wiring current i2, and if both the first wiring current i1 and the second wiring current i2 are "present", it determines that the electrical equipment 50 is in the "normal state" of not operating.

[0068] On the other hand, when the electrical equipment 50 is activated, for example by being operated, the first normally closed switch SW1 and the second normally closed switch SW2 are opened, and the first wiring current i1 and the second wiring current i2 stop flowing. As a result, the determination unit 60 of the higher-level device 102 determines that the electrical equipment is "operated" if neither the first wiring current i1 nor the second wiring current i2 is detected, and both the first wiring current i1 and the second wiring current i2 are "absent". The determination unit 60 then performs the corresponding display operation, control operation, or other processing.

[0069] Furthermore, if a break occurs in any of the first wiring circuits, excluding the external common wire 108, the first wiring current i1 will stop flowing, but the second wiring current i2 will continue to flow normally. Therefore, the determination unit 60 of the higher-level device 102 determines that there is a "break in the first wiring circuit" when the second wiring current i2 is detected and the status is "present," and the first wiring current i1 is not detected and the status is "absent," and outputs a break alarm to prompt prompt repair of the break. In this case, the break alarm is performed, for example, by sound and display, and conveys that there is a break in the first wiring circuit.

[0070] Furthermore, if a break occurs in any of the second wiring circuits, excluding the external common wire 108, the second wiring current i2 will stop flowing, but the first wiring current i1 will continue to flow normally. Therefore, the determination unit 60 of the higher-level device 102 determines that there is a "break in the second wiring circuit" when the first wiring current i1 is detected and the status is "present," and the second wiring current i2 is not detected and the status is "absent," and outputs a break alarm to prompt prompt repair of the break. In this case, the break alarm is also performed, for example, by sound and display, to inform the user that there is a break in the second wiring circuit.

[0071] Furthermore, if a break occurs in the external common wire 108, the first wiring current i1 and the second wiring current i2 will stop flowing, and therefore the first wiring current i1 and the second wiring current i2 will no longer be detected. As a result, the determination unit 60 of the higher-level device 102 will incorrectly determine that a break in the external common wire 108 is "operation of electrical equipment". For this reason, it becomes necessary to perform verification work by an operator, for example, to determine whether it is "operation of electrical equipment" or "a break in the external common wire". For example, in the case of emergency equipment, an operator will check whether an abnormality has actually occurred at the site where the fire hydrant device is installed, and if no abnormality is confirmed, it will be determined that a "break in the external common wire" has occurred.

[0072] In other words, the determination unit 60 can determine if a wire is broken in any wire other than the external common wire 108, but for a broken wire in the external common wire 108, the determination unit 60 will need to perform the determination or other necessary actions, such as verification by a worker.

[0073] In response to this, in order for the determination unit 60 to also determine if the external common wire 108 is broken, it is conceivable to use separate external common wires for the first and second wiring circuits, rather than making the external common wire 108 a common wire for both the first and second wiring circuits, as shown in Figure 5, for example. That is, the first and second wiring circuits are configured such that the external common wire 108-2 for the second wiring circuit is connected to terminal A5 of terminal block 30 without connecting terminals A5 and A7 of terminal block 30, and another external common wire 108-1 for the first wiring circuit is connected to terminal A7 of terminal block 30.

[0074] In this case, the determination unit 60 can also determine if an external common line 108 is broken. However, this would increase the number of external common lines 108, which would increase equipment costs. Therefore, the decision of whether to use a common or separate external common line 108 will be made based on the equipment and costs to which the breakage monitoring system will be applied.

[0075] (b3. Other embodiments of the determination unit) Another embodiment of the determination unit 60 that enables detection of disconnections in external common wires, without increasing the number of external common wires, will be described in more detail.

[0076] In the determination unit 60 of this embodiment, if neither the first wiring current i1 nor the second wiring current i2 is detected, and both the first wiring current i1 and the second wiring current i2 are "none", it is not determined that "electrical equipment is operating". Instead, as shown in Figures 6(A) and 6(B), terminal B of the host device 102 to which the second external signal line 106 is connected is switched from a terminal with (+) polarity for applying a wiring voltage between the second external signal line 106 and the external common line 108 to a terminal with (-) polarity for applying a wiring voltage between the first external signal line 104 and the second external signal line 106. Based on the state of the third wiring current i3 flowing through the third wiring circuit that forms a loop line including the first external signal line 104 and the second external signal line 106, it is further determined whether "electrical equipment is operating" or "the external common line is disconnected".

[0077] Here, the path of the third wiring circuit forming the loop line is indicated by symbols as follows: [Terminal A of the higher-level device 102]-[First external signal line 104]-[Terminal A1 of the terminal block 30]-[First termination resistor 36]-[Terminal A2 of the terminal block 30]-[First internal wiring]-[First normally closed switch SW1]-[First internal wiring]-[Terminal A8 of the terminal block 30]-[Terminal A7 of the terminal block 30]-[Terminal A5 of the terminal block 30]-[Terminal A6 of the terminal block 30]-[Second internal wiring]-[Second normally closed switch SW2]-[Second internal wiring]-[Terminal A4 of the terminal block 30]-[Second termination resistor 38]-[Terminal A3 of the terminal block 30]-[Second external signal line 106]-[Terminal B of the higher-level device 102].

[0078] Thus, as shown in Figure 6(A), when the electrical equipment 50 is operating and the first normally closed switch SW1 and the second normally closed switch SW2 are open, the path of the third wiring circuit is interrupted by the first normally closed switch SW1 and the second normally closed switch SW2, which are open, so no current i3 flows through the third wiring circuit.

[0079] In contrast, as shown in Figure 6(B), if the external common wire 108 is disconnected, the path of the third wiring circuit is not interrupted, and a loop line is formed, so the third wiring current i3 flows from terminal A to terminal B of the higher-level device 102.

[0080] Therefore, after the determination unit 60 switches the voltage polarity of terminal B to which the second external signal line 106 is connected from (+) to (-), if the third wiring current i3 is not detected and the state is "absent", it determines that "electrical equipment is operating", and if the third wiring current i3 is detected and the state is "present", it determines that "external common wire is broken".

[0081] Figure 7 shows the determination process by the determination unit 60 of this embodiment. Figure 7(A) shows the case where the voltage polarity of terminal B to which the second external signal line 106 is connected is (+), and the determination is made based on the state of the first wiring current i1 of the first wiring circuit and the second wiring current i2 of the second wiring circuit. The determination of the "normal state" is the same as the determination process shown in Figure 4. However, when the first wiring current i1 and the second wiring current i2 are "none", the state is determined to be "undefined". In this embodiment, a "disconnection of the external common wire" can be determined, so the determination of "disconnection of the first wiring circuit" and "disconnection of the second wiring circuit" in Figure 4 is changed to "disconnection of a wire other than the external common wire of the first wiring circuit" and "disconnection of a wire other than the external common wire of the second wiring circuit", which is different from the determination process shown in Figure 4.

[0082] Then, if the determination unit 60 determines that the value is "undetermined", as shown in Figure 7(B), the voltage polarity of terminal B to which the second external signal line 106 is connected is switched from (+) to (-) to form a third wiring circuit. If the third wiring current i3 is "present", it is determined that "the external common wire is broken", and if the wiring current i3 is "absent", it is determined that "the electrical equipment is operating".

[0083] Therefore, the determination unit 60 of this embodiment can determine "disconnection of an external common wire" separately from "operation of electrical equipment," making it possible to avoid increasing the number of external common wires and eliminating the need for on-site verification by workers.

[0084] In this embodiment, if the determination unit 60 determines that both the first wiring current i1 and the second wiring current i2 are in a "none" state and are therefore "undefined", it switches the voltage polarity of terminal B to which the second external signal line 106 is connected from (+) to (-). However, it is also possible to switch the voltage polarity of terminal A to which the first external signal line 104 is connected from (+) to (-) to form a third wiring circuit, and determine whether "electrical equipment is operating" or "the external common wire is broken" based on the state of the third wiring current i3 flowing from terminal B to terminal A.

[0085] [c. Second embodiment of the wire breakage monitoring system] Next, a second embodiment of the wire breakage monitoring system will be described in more detail, using as an example a system in which electrical equipment, one unit at each of multiple terminal devices, is connected in stages to a higher-level device. Figure 8 shows an example of a wiring circuit diagram of the wire breakage monitoring system. Here, the explanation assumes that the wiring is connected to the switches provided by the electrical equipment.

[0086] As shown in Figure 8, for example, a first external signal line 104, a second external signal line 106, and an external common line 108 are drawn out from the upper-level device 102 as external wiring to the terminal device, and two terminal devices 100(100-1) and 100(100-2) are connected in stages. Here, terminal device 100(100-1) is the first stage, and terminal device 100(100-2) is the final stage. In this embodiment, a first wiring circuit including the first external signal line 104 and the external common line 108, and a second wiring circuit including the second external signal line 106 and the external common line 108 are configured.

[0087] Furthermore, each of the terminal devices 100(100-1) and 100(100-2) is provided with electrical equipment 50 and a terminal block 30, and the electrical equipment 50 is provided with a first normally closed switch SW1 and a second normally closed switch SW2 that are linked to a predetermined operation, such as a push button operation.

[0088] Since terminal devices 100(100-1), 100(100-2), and host device 102 are basically the same as terminal device 100 and host device 102 shown in Figure 3(A), they are given the same reference numerals and their descriptions are omitted.

[0089] The differences between terminal device 100(100-1) and terminal device 100 shown in Figure 3 are that the first termination resistor 36 is not provided between terminals A1 and A2 of terminal block 30, the second termination resistor 38 is not provided between terminals A3 and A4, there is no connection between terminals A5 and A7 of terminal block 30, the second external signal line 106 which connects to terminal A3 of terminal device 100(100-2) is connected to terminal A5, and the first external signal line 104 which connects to terminal A1 of terminal device 100(100-2) is connected to terminal A7. Although the first termination resistor 36 and the second termination resistor 38 are provided between terminals A1 and A2 or between A3 and A4 of terminal block 30 of terminal device 100(100-2), the connection position of the first termination resistor 36 and the second termination resistor 38 may be any position on each loop line, as in the first embodiment.

[0090] The first wiring circuit is configured such that the first external signal line 104 from terminal A of the upper-level device 102 is connected to terminal A1 of the terminal block 30 of the first-stage terminal device 100 (100-1), the external common line 108 to terminal C of the upper-level device 102 is connected to terminal A7 of the terminal block 30 of the final-stage terminal device 100 (100-2), the first internal wiring from terminal A2 of each terminal block 30 is connected to one terminal of the first normally closed switch SW1, the first internal wiring to terminal A8 of each terminal block 30 is connected to the other terminal of the first normally closed switch SW1, and terminal A7 of the terminal block 30 of the first-stage terminal device 100 (100-1) and terminal A1 of the terminal block 30 of the final-stage terminal device 100 (100-2) are connected by the first external signal line 104, thereby forming a loop line that passes through all the first normally closed switches SW1 and the first termination resistor 36.

[0091] The second wiring circuit is configured such that the second external signal line 106 from terminal B of the upper-level device 102 is connected to terminal A3 of the terminal block 30 of the first-stage terminal device 100 (100-1), the external common line 108 to terminal C of the upper-level device 102 is connected to terminal A5 of the terminal block 30 of the final-stage terminal device 100 (100-2) via terminal A7, and the second internal wiring from terminal A4 of each terminal block 30 is connected to one side of the second normally closed switch SW2. The terminals are connected, and the second internal wiring to terminal A6 of each terminal block 30 is connected to the other terminal of the second normally closed switch SW2. Terminal A5 of the terminal block 30 of the first stage terminal device 100 (100-1) and terminal A3 of the terminal block 30 of the final stage terminal device 100 (100-2) are connected by the second external signal line 106, thereby forming a loop line that passes through all the second normally closed switches SW2 and the second termination resistors 38.

[0092] Here, the path of the first wiring circuit that forms a loop line passing through all the first normally closed switches SW1 and the first termination resistor 36 is indicated by symbols as follows: [Terminal A of the upper device 102]-[First external signal line 104]-[Terminal A1 of the terminal block 30 of the terminal device 100(100-1)]-[Terminal A2 of the terminal block 30 of the terminal device 100(100-1)]-[First internal wiring]-[First normally closed switch SW1 of the electrical equipment 50 of the terminal device 100(100-1)]-[First internal wiring]-[Terminal A8 of the terminal block 30 of the terminal device 100(100-1)]-[Terminal device 100(10 The connections are as follows: Terminal A7 of terminal block 30 of terminal 100 (100-2) - [First external signal line 104] - [Terminal A1 of terminal block 30 of terminal device 100 (100-2)] - [First termination resistor 36] - [Terminal A2 of terminal block 30 of terminal device 100 (100-2)] - [First internal wiring] - [First normally closed switch SW1 of electrical equipment 50 of terminal device 100 (100-2)] - [First internal wiring] - [Terminal A8 of terminal block 30 of terminal device 100 (100-2)] - [Terminal A7 of terminal block 30 of terminal device 100 (100-2)] - [External common line 108] - [Terminal C of host device 102].

[0093] Furthermore, the path of the second wiring circuit that forms a loop line passing through all the second normally closed switches SW2 and the second termination resistor 38 is indicated by symbols as follows: [Terminal B of the upper device 102]-[Second external signal line 106]-[Terminal A3 of the terminal block 30 of the terminal device 100 (100-1)]-[Terminal A4 of the terminal block 30 of the terminal device 100 (100-1)]-[Second internal wiring]-[Second normally closed switch SW2 of the electrical equipment 50 of the terminal device 100 (100-1)]-[Second internal wiring]-[Terminal A6 of the terminal block 30 of the terminal device 100 (100-1)]-[Terminal A5 of the terminal block 30 of the terminal device 100 (100-1)] ]-[Second external signal line 106]-[Terminal A3 of terminal block 30 of terminal device 100 (100-2)]-[Second termination resistor 38]-[Terminal A4 of terminal block 30 of terminal device 100 (100-2)]-[Second internal wiring]-[Second normally closed switch SW2 of electrical equipment 50 of terminal device 100 (100-2)]-[Second internal wiring]-[Terminal A6 of terminal block 30 of terminal device 100 (100-2)]-[Terminal A5 of terminal block 30 of terminal device 100 (100-2)]-[Terminal A7 of terminal block 30 of terminal device 100 (100-2)]-[External common line 108]-[Terminal C of host device 102].

[0094] The determination unit 60 of the higher-level device 102 performs a determination process similar to the determination process shown in the table in Figure 4, based on the first wiring current i1 of the first wiring circuit and the second wiring current i2 of the second wiring circuit.

[0095] First, under normal conditions, the first normally closed switch SW1 and the second normally closed switch SW2 of the terminal devices 100(100-1) and 100(100-2) are closed, and if there are no open circuits in the first and second wiring circuits, the first wiring current i1 and the second wiring current i2 flow normally. For this reason, the determination unit 60 of the higher-level device 102 detects the first wiring current i1 and the second wiring current i2, and if both the first wiring current i1 and the second wiring current i2 are "present", it determines that the electrical equipment 50 of the terminal devices 100(100-1) and 100(100-2) are in a non-operating "normal state".

[0096] On the other hand, if the electrical equipment 50 of terminal device 100 (100-1) is operated, for example, the first normally closed switch SW1 and the second normally closed switch SW2 of the electrical equipment 50 are opened, and the first wiring current i1 and the second wiring current i2 stop flowing. Therefore, if the determination unit 60 of the higher-level device 102 does not detect the first wiring current i1 and the second wiring current i2, and both the first wiring current i1 and the second wiring current i2 become "none", it determines that "electrical equipment has been operated" and performs the corresponding display operation or control operation. The same applies when the electrical equipment 50 of terminal device 100 (100-2) is operated.

[0097] Furthermore, if a break occurs in any of the first wiring circuits, excluding the external common wire 108, the first wiring current i1 will stop flowing, but the second wiring current i2 will flow normally. For this reason, the determination unit 60 of the higher-level device 102 determines that there is a "break in the first wiring circuit" when the second wiring current i2 is "present" and the first wiring current i1 is "absent," and outputs a break alarm to prompt a quick repair response to the break. In this case, the break alarm is performed, for example, by sound and display, and conveys that there is a break in the first wiring circuit.

[0098] Furthermore, if a break occurs in any of the second wiring circuits, excluding the external common wire 108, the second wiring current i2 will stop flowing, but the first wiring current i1 will flow normally. For this reason, the determination unit 60 of the higher-level device 102 determines that there is a "break in the second wiring circuit" when the first wiring current i1 is "present" and the second wiring current i2 is "absent," and outputs a break alarm to prompt a quick repair response to the break. This break alarm is also performed, for example, by sound and display, to indicate that there is a break in the second wiring circuit.

[0099] Furthermore, if a break occurs in the external common wire 108, the first wiring current i1 and the second wiring current i2 will stop flowing, and therefore the first wiring current i1 and the second wiring current i2 will no longer be detectable. As with the first embodiment, it will be necessary to perform a check by an operator or similar procedure to determine whether the problem is "operation of electrical equipment" or "a break in the external common wire." Furthermore, in order for the determination unit 60 to also determine if the external common wire 108 is broken, the external common wires 108 of the first wiring circuit and the second wiring circuit may be made into separate external common wires 108-1 and 108-2, as shown in Figure 9, similar to the first embodiment.

[0100] Furthermore, even in the second embodiment, the determination unit 60 may apply other embodiments of the determination unit shown in the first embodiment to perform a determination process similar to the determination process shown in Figure 7, thereby enabling it to determine whether the electrical equipment is operating or whether there is a break in the external common wire. Also, other embodiments of the determination unit in the second embodiment are basically the same as other embodiments of the determination unit shown in the first embodiment, but the third wiring circuit that is formed will be different.

[0101] [d. Third embodiment of the wire breakage monitoring system] Next, a third embodiment of the wire breakage monitoring system will be described in more detail, using as an example a system in which multiple electrical devices located on a single terminal device are connected to a higher-level device. Figure 10 shows an example of a wiring circuit diagram of the wire breakage monitoring system, and Figure 11 shows a schematic of the wiring to the terminals of the terminal block used in the third embodiment. Furthermore, this explanation assumes that the wiring is connected to the switches provided by the electrical devices.

[0102] As shown in Figure 10(A), for example, terminal device 100 is equipped with two electrical devices 50(50-1) and 50(50-2). From the higher-level device 102, a first external signal line 104 and a second external signal line 106 are drawn to electrical device 50(50-1), a first external signal line 114 and a second external signal line 116 are drawn to electrical device 50(50-2), and a common external line 108 is drawn to both electrical devices 50(50-1) and 50(50-2).

[0103] In this embodiment, a first wiring circuit including a first external signal line 104 and an external common line 108 is configured for electrical equipment 50 (50-1), and a second wiring circuit including a second external signal line 106 and an external common line 108 is configured for electrical equipment 50 (50-2). A first wiring circuit including a first external signal line 114 and an external common line 108 is configured for electrical equipment 50 (50-2), and a second wiring circuit including a second external signal line 116 and an external common line 108 is configured for electrical equipment 50 (50-2). Here, the connection terminals for the first external signal line 104, the second external signal line 106, the first external signal line 114, the second external signal line 116, and the external common line 108 in the host device 102 are designated as terminals A, B, C, D, and E, respectively.

[0104] The configuration of the switches in electrical equipment 50 (50-1) and the connection of the internal wiring to the terminal block 30 are the same as in the case of terminal device 100 in Figure 3(A), so the same reference numerals are used and their explanation is omitted. Also, the configuration of the switches in electrical equipment 50 (50-2) and the connection of the internal wiring to the terminal block 30 are basically the same as in the case of terminal device 100 in Figure 3(A), however, in the case of the switches, the reference numerals for the first normally closed switch and the second normally closed switch are SW3 and SW4, and in the case of the connection of the internal wiring to the terminal block 30, it is connected to terminals A9 to A16 of the terminal block 30.

[0105] Furthermore, in the structure of the terminal block 30 of this embodiment, for example as shown in Figure 11, terminals A1 to A16 are arranged in a row, a first termination resistor 36 is connected between terminals A1 and A2, a second termination resistor 38 is connected between terminals A3 and A4, a first termination resistor 40 is connected between terminals A9 and A10, a second termination resistor 42 is connected between terminals A11 and A12, and terminals A5 and A7, A7 and A13, and A13 and A15 are connected.

[0106] Therefore, the path of the first wiring circuit that forms a loop line via the first normally closed switch SW1 and the first termination resistor 36 for the electrical equipment 50 (50-1) can be shown by symbols as follows: [Terminal A of the higher-level device 102]-[First external signal line 104]-[Terminal A1 of the terminal block 30]-[First termination resistor 36]-[Terminal A2 of the terminal block 30]-[First internal wiring]-[First normally closed switch SW1 of the electrical equipment 50 (50-1)]-[First internal wiring]-[Terminal A8 of the terminal block 30]-[Terminal A7 of the terminal block 30]-[Terminal A13 of the terminal block 30]-[Terminal A15 of the terminal block 30]-[External common line 108]-[Terminal E of the higher-level device 102].

[0107] Furthermore, the path of the second wiring circuit that forms a loop line via the second normally closed switch SW2 and the second termination resistor 38 for the electrical equipment 50 (50-1) is indicated by symbols as follows: [Terminal B of the higher-level device 102]-[Second external signal line 106]-[Terminal A3 of the terminal block 30]-[Second termination resistor 38]-[Terminal A4 of the terminal block 30]-[Second internal wiring]-[Second normally closed switch SW2 of the electrical equipment 50 (50-1)]-[Second internal wiring]-[Terminal A6 of the terminal block 30]-[Terminal A5 of the terminal block 30]-[Terminal A7 of the terminal block 30]-[Terminal A13 of the terminal block 30]-[Terminal A15 of the terminal block 30]-[External common line 108]-[Terminal E of the higher-level device 102].

[0108] Furthermore, the path of the first wiring circuit that forms a loop line via the first normally closed switch SW3 and the first termination resistor 40 for the electrical equipment 50 (50-2) is indicated by symbols as follows: [Terminal C of the higher-level device 102]-[First external signal line 114]-[Terminal A9 of the terminal block 30]-[First termination resistor 40]-[Terminal A10 of the terminal block 30]-[First internal wiring]-[First normally closed switch SW3 of the electrical equipment 50 (50-2)]-[First internal wiring]-[Terminal A16 of the terminal block 30]-[Terminal A15 of the terminal block 30]-[External common line 108]-[Terminal E of the higher-level device 102].

[0109] Furthermore, the path of the second wiring circuit that forms a loop line via the second normally closed switch SW4 and the second termination resistor 42 for the electrical equipment 50 (50-2) is indicated by symbols as follows: [Terminal D of the higher-level device 102]-[Second external signal line 116]-[Terminal A11 of the terminal block 30]-[Second termination resistor 42]-[Terminal A12 of the terminal block 30]-[Second internal wiring]-[Second normally closed switch SW4 of the electrical equipment 50 (50-2)]-[Second internal wiring]-[Terminal A14 of the terminal block 30]-[Terminal A13 of the terminal block 30]-[Terminal A15 of the terminal block 30]-[External common line 108]-[Terminal E of the higher-level device 102].

[0110] Furthermore, the connection positions of the first termination resistors 36 and 40 and the second termination resistors 38 and 42 may be at any position on each loop line, as in the embodiment described above.

[0111] The determination unit 60 of the higher-level device 102 performs a determination process similar to the determination process shown in Figure 4, based on the first wiring current i11 of the first wiring circuit and the second wiring current i12 of the second wiring circuit for the electrical equipment 50 (50-1), and determines whether the state is normal, whether the electrical equipment 50 (50-1) is operating, whether the first wiring circuit for the electrical equipment 50 (50-1) is open, and whether the second wiring circuit is open.

[0112] Furthermore, the determination unit 60 of the higher-level device 102 performs a determination process similar to the determination process shown in Figure 4, based on the first wiring current i21 of the first wiring circuit and the second wiring current i22 of the second wiring circuit for the electrical equipment 50 (50-2), and determines whether the state is normal, whether the electrical equipment 50 (50-2) is operating, whether the first wiring circuit for the electrical equipment 50 (50-2) is open, and whether the second wiring circuit is open.

[0113] Furthermore, similar to the embodiments described above, in order to determine if a break occurs in the external common line 108, separate external common lines 108-1 and 108-2 may be wired corresponding to the first external signal lines 104 and 114 and the second external signal lines 106 and 116, as shown in Figure 12.

[0114] Furthermore, even in the third embodiment, the determination unit 60 may apply other embodiments of the determination unit shown in the first embodiment to perform a determination process similar to the determination process shown in Figure 7, so that it can determine whether it is "operation of electrical equipment" or "disconnection of the external common wire". Also, in the third embodiment, unlike the first and second embodiments, the host device 102 has five terminals, and there are two first external signal lines and two second external signal lines connected to the host device 102, so it is as follows.

[0115] In the determination unit 60 of this embodiment, if the first wiring current i11 of the first wiring circuit and the second wiring current i12 of the second wiring circuit for the electrical equipment 50 (50-1) are not detected, and both the first wiring current i11 and the second wiring current i12 are "none", the determination unit 60 does not determine that "the electrical equipment 50 (50-1) is operating", and instead, as shown in Figures 10(A) and (B), it determines that terminal B of the host device 102 to which the second external signal line 106 is connected is connected to the second external signal line 106 and the external cable. The terminal is switched from a (+) polarity terminal for applying a wiring voltage between wires 108 to a (-) polarity terminal for applying a wiring voltage between the first external signal line 104 and the second external signal line 106. Based on the state of the third wiring current i13 flowing through the third wiring circuit that forms a loop line including the first external signal line 104 and the second external signal line 106, it is further determined whether the electrical equipment 50 (50-1) is operating or the external common wire is broken.

[0116] Furthermore, if the first wiring current i21 of the first wiring circuit and the second wiring current i22 of the second wiring circuit for the electrical equipment 50 (50-2) are not detected, and both the first wiring current i21 and the second wiring current i22 are "none", it is not determined that the electrical equipment 50 (50-2) is "operating". Instead, as shown in Figures 10(A) and (B), terminal D of the upper-level device 102 to which the second external signal line 116 is connected is switched from a terminal with (+) polarity for applying a wiring voltage between the second external signal line 116 and the external common line 108 to a terminal with (-) polarity for applying a wiring voltage between the first external signal line 114 and the second external signal line 116. Based on the state of the third wiring current i23 flowing through the third wiring circuit that forms a loop line including the first external signal line 114 and the second external signal line 116, a determination is made as to whether the electrical equipment 50 (50-2) is "operating" or whether the "external common line is broken".

[0117] Here, the path of the third wiring circuit to the electrical equipment 50 (50-1) is indicated by symbols as follows: [Terminal A of the higher-level device 102]-[First external signal line 104]-[Terminal A1 of the terminal block 30]-[First termination resistor 36]-[Terminal A2 of the terminal block 30]-[First internal wiring]-[First normally closed switch SW1 of the electrical equipment 50 (50-1)]-[First internal wiring]-[Terminal A8 of the terminal block 30]-[Terminal A7 of the terminal block 30]-[Terminal A5 of the terminal block 30]-[Terminal A6 of the terminal block 30]-[Second internal wiring]-[Second normally closed switch SW2 of the electrical equipment 50 (50-1)]-[Second internal wiring]-[Terminal A4 of the terminal block 30]-[Second termination resistor 38]-[Terminal A3 of the terminal block 30]-[Second external signal line 106]-[Terminal B of the higher-level device 102].

[0118] Furthermore, the path of the third wiring circuit to the electrical equipment 50 (50-2) is indicated by symbols as follows: [Terminal C of the higher-level device 102] - [First external signal line 114] - [Terminal A9 of the terminal block 30] - [First termination resistor 40] - [Terminal A10 of the terminal block 30] - [First internal wiring] - [First normally closed switch SW3 of the electrical equipment 50 (50-2)] - [First internal wiring] - [Terminal A16 of the terminal block 30] ]-[Terminal block 30 terminal A15]-[Terminal block 30 terminal A13]-[Terminal block 30 terminal A14]-[Second internal wiring]-[Second normally closed switch SW2 of electrical equipment 50 (50-2)]-[Second internal wiring]-[Terminal block 30 terminal A12]-[Second termination resistor 42]-[Terminal block 30 terminal A11]-[Second external signal line 116]-[Terminal D of host device 102].

[0119] Thus, the third wiring circuit for the electrical equipment 50(50-1), which is formed by switching the voltage polarity of terminal B to which the second external signal line 106 is connected from (+) to (-), does not allow the third wiring current i13 to flow when the electrical equipment 50(50-1) is operating and the first normally closed switch SW1 and the second normally closed switch SW2 are open, because the path is interrupted by the first normally closed switch SW1 and the second normally closed switch SW2 of the electrical equipment 50(50-1) whose third wiring circuit is open.

[0120] Furthermore, the third wiring circuit for the electrical equipment 50(50-2), which is formed by switching the voltage polarity of terminal D to which the second external signal line 116 is connected from (+) to (-), does not allow the third wiring current i23 to flow when 50(50-2) is operating and the first normally closed switch SW3 and the second normally closed switch SW4 are open, because the path is interrupted by the first normally closed switch SW3 and the second normally closed switch SW4 of the electrical equipment 50(50-2) whose third wiring circuit is open.

[0121] In contrast, if the external common wire 108 is disconnected, the path of the third wiring circuit to the electrical equipment 50(50-1) and 50(50-2) is not interrupted, and a loop line is formed. As a result, the third wiring current i13 flows from terminal A to terminal B of the higher-level device 102, and the third wiring current i23 flows from terminal C to terminal D of the higher-level device 102.

[0122] Therefore, after the determination unit 60 switches the voltage polarity of terminal B to which the second external signal line 106 is connected from (+) to (-), if the third wiring current i13 is not detected and the state is "none", it determines that "electrical equipment 50 (50-1) is operating", and if the current i13 is detected and the state is "present", it determines that "external common wire is broken".

[0123] Furthermore, after the determination unit 60 switches the voltage polarity of terminal D to which the second external signal line 116 is connected from (+) to (-), if the third wiring current i23 is not detected and the state is "none", it determines that "electrical equipment 50 (50-2) is operating", and if current i13 is detected and the state is "present", it determines that "external common wire is broken".

[0124] Therefore, the determination unit 60 of the higher-level device 102 can determine "disconnection of an external common wire" separately from "operation of electrical equipment 50 (50-1)" or "operation of electrical equipment 50 (50-2)," making it possible to avoid increasing the number of external common wires and eliminating the need for on-site verification by workers.

[0125] In this embodiment, the determination unit 60 switches the voltage polarity of terminal B to which the second external signal line 106 is connected from (+) to (-). However, the voltage polarity of terminal A to which the first external signal line 104 is connected may be switched from (+) to (-) to form a third wiring circuit, and the state of the third wiring current i13 flowing from terminal B to terminal A may be used to determine whether "electrical equipment 50 (50-1) is operating" or "the external common wire is broken."

[0126] Furthermore, although the determination unit 60 was configured to switch the voltage polarity of terminal D to which the second external signal line 116 is connected from (+) to (-), it may also be configured to switch the voltage polarity of terminal C to which the first external signal line 114 is connected from (+) to (-) to form a third wiring circuit, and determine whether "electrical equipment 50 (50-2) is operating" or "the external common wire is broken" based on the state of the third wiring current i23 flowing from terminal D to terminal C.

[0127] [e. Fourth embodiment of the wire breakage monitoring system] Next, the fourth embodiment of the wire breakage monitoring system will be described in more detail, using as an example a system in which multiple electrical devices, each arranged as a terminal device to a higher-level device, are connected in groups in a stepwise manner. Figure 13 shows an example of a wiring circuit diagram of the wire breakage monitoring system according to the fourth embodiment, and corresponds to an embodiment that combines the second and third embodiments described above.

[0128] As shown in Figure 13, for example, each of the terminal devices 100(100-1) and 100(100-2) is provided with electrical equipment 50(50-1) and 50(50-2), and a first external signal line 104 and a second external signal line 106 are drawn from the upper-level device 102 to the electrical equipment 50(50-1) of the terminal devices 100(100-1) and 100(100-2), a first external signal line 114 and a second external signal line 116 are drawn from the electrical equipment 50(50-2) of the terminal devices 100(100-1) and 100(100-2), and a common external line 108 is drawn from the electrical equipment 50(50-1) and 50(50-2). Here, terminal device 100(100-1) is the first stage, and terminal device 100(100-2) is the final stage. Also, the electrical equipment 50(50-1) of terminal devices 100(100-1) and 100(100-2) belong to one group, and the electrical equipment 50(50-2) of terminal devices 100(100-1) and 100(100-2) belong to one group.

[0129] In this embodiment, a first wiring circuit including a first external signal line 104 and an external common line 108 is configured for the electrical equipment 50(50-1) of terminal devices 100(100-1) and 100(100-2), and a second wiring circuit including a second external signal line 106 and an external common line 108 is configured for the electrical equipment 50(50-2) of terminal devices 100(100-1) and 100(100-2). A first wiring circuit including a first external signal line 114 and an external common line 108 is configured for the electrical equipment 50(50-2) of terminal devices 100(100-1) and 100(100-2), and a second wiring circuit including a second external signal line 116 and an external common line 108 is configured for the electrical equipment 50(50-2) of terminal devices 100(100-1) and 100(100-2).

[0130] Furthermore, electrical equipment 50(50-1) is provided with a first normally closed switch SW1 and a second normally closed switch SW2 that are linked to a predetermined operation, such as a push button operation, and electrical equipment 50(50-2) is provided with a first normally closed switch SW3 and a second normally closed switch SW4 that are linked in the same way as electrical equipment 50(50-1).

[0131] Since terminal devices 100(100-1), 100(100-2), and host device 102 are basically the same as terminal device 100 and host device 102 shown in Figure 10, they are given the same reference numerals and their descriptions are omitted.

[0132] The differences between terminal device 100 (100-1) and terminal device 100 shown in Figure 10 are that a first termination resistor 36 is not provided between terminals A1 and A2 of terminal block 30, a second termination resistor 38 is not provided between terminals A3 and A4, a first termination resistor 40 is not provided between terminals A9 and A10, a second termination resistor 42 is not provided between terminals A11 and A12, and between terminals A5 and A7, and between terminals A7 and A13 of terminal block 30. In this configuration, terminals A13 and A15 are not connected, a second external signal line 106 is connected to terminal A3 of terminal device (100-2) at terminal A5, a first external signal line 104 is connected to terminal A1 of terminal device (100-2) at terminal A7, a second external signal line 116 is connected to terminal A11 of terminal device (100-2) at terminal A13, and a first external signal line 114 is connected to terminal A9 of terminal device (100-2) at terminal A15.

[0133] The difference between terminal device (100-2) and terminal device 100 shown in Figure 10 lies in the wiring circuit for the external common line 108. In this embodiment, the terminals of the first normally closed switch SW1, SW3 and the second normally closed switches SW2, SW4 on the side connected to the external common line 108 are connected by internal wiring, the terminal of the first normally closed switch SW1 is connected to terminal A8 of the terminal block 30 by internal wiring, and terminal A8 is connected to terminal A7 to which the external common line 108 is connected, thereby forming a wiring circuit for the external common line 108.

[0134] By using this wiring circuit, the number of terminals used in the terminal block 30 can be reduced to 10, allowing the use of a terminal block with fewer terminals and thus reducing equipment costs. On the other hand, the wiring locations that the determination unit 60 cannot determine as having a break in the wire will include not only the external common wire 108 but also the internal wiring between the terminal of the first normally closed switch SW1 and terminal A8 of the terminal block 30.

[0135] Therefore, similar to the terminal device 100 shown in Figure 10, the internal wiring from each normally closed switch to the terminal block 30 may be separate internal wiring for each normally closed switch. Also, regarding the external common wire 108, instead of using a common external common wire as in the embodiment described above, separate external common wires may be used to form the wiring circuits.

[0136] Therefore, the path of the first wiring circuit that forms a loop line passing through the first normally closed switch SW1 and the first termination resistor 36 of the electrical equipment 50 (50-1) of terminal device (100-1) and 100 (100-2) is shown by symbols as follows: [Terminal A of the higher-level device 102] - [First external signal line 104] - [Terminal A1 of the terminal block 30 of terminal device 100 (100-1)] - [Terminal A2 of the terminal block 30 of terminal device 100 (100-1)] - [First internal wiring] - [First normally closed switch SW1 of the electrical equipment 50 (50-1) of terminal device 100 (100-1)] - [First internal wiring] - [Terminal block 30 of terminal device 100 (100-1)] The connections are as follows: Terminal A8] - [Terminal A7 of terminal block 30 of terminal device 100 (100-1)] - [First external signal line 104] - [Terminal A1 of terminal block 30 of terminal device 100 (100-2)] - [First termination resistor 36] - [Terminal A2 of terminal block 30 of terminal device 100 (100-2)] - [First internal wiring] - [First normally closed switch SW1 of electrical equipment 50 (50-1) of terminal device 100 (100-2)] - [First internal wiring] - [Terminal A8 of terminal block 30 of terminal device 100 (100-2)] - [Terminal A7 of terminal block 30 of terminal device 100 (100-2)] - [External common line 108] - [Terminal E of host device 102].

[0137] Furthermore, the path of the second wiring circuit that forms a loop line passing through the second normally closed switch SW2 and the second termination resistor 38 of the electrical equipment 50 (50-1) of terminal device (100-1) and 100 (100-2) is shown by symbols as follows: [Terminal B of upper-level device 102]-[Second external signal line 106]-[Terminal A3 of terminal block 30 of terminal device 100 (100-1)]-[Terminal A4 of terminal block 30 of terminal device 100 (100-1)]-[Second internal wiring]-[Second normally closed switch SW2 of electrical equipment 50 (50-1) of terminal device 100 (100-1)]-[Second internal wiring]-[Terminal block 30 of terminal device 100 (100-1) The connections are as follows: Terminal A6] - [Terminal A5 of terminal block 30 of terminal device 100 (100-1)] - [Second external signal line 106] - [Terminal A3 of terminal block 30 of terminal device 100 (100-2)] - [Second termination resistor 38] - [Terminal A4 of terminal block 30 of terminal device 100 (100-2)] - [Second internal wiring] - [Second normally closed switch SW2 of electrical equipment 50 (50-1) of terminal device 100 (100-2)] - [Internal wiring] - [Terminal A8 of terminal block 30 of terminal device 100 (100-2)] - [Terminal A7 of terminal block 30 of terminal device 100 (100-2)] - [External common line 108] - [Terminal E of host device 102].

[0138] Furthermore, the path of the first wiring circuit that forms a loop line passing through the first normally closed switch SW3 and the first termination resistor 40 of the electrical equipment 50 (50-2) of terminal devices (100-1) and 100 (100-2) is shown by symbols as follows: [Terminal C of the higher-level device 102] - [First external signal line 114] - [Terminal A9 of the terminal block 30 of terminal device 100 (100-1)] - [Terminal A10 of the terminal block 30 of terminal device 100 (100-1)] - [First internal wiring] - [First normally closed switch SW3 of the electrical equipment 50 (50-2) of terminal device 100 (100-1)] - [First internal wiring] - [Terminal of the terminal block 30 of terminal device 100 (100-1)] The connections are as follows: A16]-[Terminal A15 of terminal block 30 of terminal device 100 (100-1)]-[First external signal line 114]-[Terminal A9 of terminal block 30 of terminal device 100 (100-2)]-[First termination resistor 40]-[Terminal A10 of terminal block 30 of terminal device 100 (100-2)]-[First internal wiring]-[First normally closed switch SW3 of electrical equipment 50 (50-2) of terminal device 100 (100-2)]-[First internal wiring]-[Terminal A8 of terminal block 30 of terminal device 100 (100-2)]-[Terminal A7 of terminal block 30 of terminal device 100 (100-2)]-[External common line 108]-[Terminal E of host device 102].

[0139] Furthermore, the path of the second wiring circuit that forms a loop line passing through the second normally closed switch SW4 and the second termination resistor 42 of the electrical equipment 50 (50-2) of terminal device (100-1) and 100 (100-2) is shown by symbols as follows: [Terminal D of upper-level device 102] - [Second external signal line 116] - [Terminal A11 of terminal block 30 of terminal device 100 (100-1)] - [Terminal A12 of terminal block 30 of terminal device 100 (100-1)] - [Second internal wiring] - [Second normally closed switch SW4 of electrical equipment 50 (50-2) of terminal device 100 (100-1)] - [Second internal wiring] - [Terminal of terminal block 30 of terminal device 100 (100-1)] A14]-[Terminal A13 of terminal block 30 of terminal device 100 (100-1)]-[Second external signal line 116]-[Terminal A11 of terminal block 30 of terminal device 100 (100-2)]-[Second termination resistor 42]-[Terminal A12 of terminal block 30 of terminal device 100 (100-2)]-[Second internal wiring]-[Second normally closed switch SW4 of electrical equipment 50 (50-2) of terminal device 100 (100-2)]-[Second internal wiring]-[Terminal A8 of terminal block 30 of terminal device 100 (100-2)]-[Terminal A7 of terminal block 30 of terminal device 100 (100-2)]-[External common line 108]-[Terminal E of host device 102].

[0140] Furthermore, the connection positions of the first termination resistors 36 and 40 and the second termination resistors 38 and 42 may be at any position on each loop line, as in the embodiment described above.

[0141] The determination unit 60 of the higher-level device 102 performs a determination process similar to the determination process shown in Figure 4, based on the first wiring current i11 of the first wiring circuit and the second wiring current i12 of the second wiring circuit for the electrical equipment 50(50-1) of the terminal devices 100(100-1) and 100(100-2), and determines whether the state is normal, the electrical equipment 50(50-1) is operating, the first wiring circuit for the electrical equipment 50(50-1) is open, and the second wiring circuit is open.

[0142] Furthermore, the determination unit 60 of the higher-level device 102 performs a determination process similar to the determination process shown in Figure 4, based on the first wiring current i21 of the first wiring circuit and the second wiring current i22 of the second wiring circuit for the electrical equipment 50(50-2) of the terminal devices 100(100-1) and 100(100-2), and determines whether the state is normal, whether the electrical equipment 50(50-2) is operating, whether the first wiring circuit for the electrical equipment 50(50-2) is open, and whether the second wiring circuit is open.

[0143] Furthermore, similar to the embodiment described above, the internal wiring from each normally closed switch to the terminal block 30 for connecting to the external common line 108 may be made into separate internal wiring, so that the only wiring location where a break in the external common line 108 cannot be detected is the external common line 108.

[0144] Furthermore, similar to the embodiments described above, in order to determine if a disconnection occurs in the external common wire 108, separate external common wires 108-1 and 108-2 may be wired corresponding to the first external signal lines 104 and 114 and the second external signal lines 106 and 116, as shown in Figure 14. Also, although Figure 14 shows separate internal wiring from each normally closed switch to the terminal block 30, as shown in Figure 15, the terminal of SW1 of the electrical equipment 50 (50-1) and the terminal of SW3 of the electromechanical equipment 50 (50-2) may be connected by internal wiring, and the wiring from the terminal of one SW (SW1 in Figure 15) to the terminal block 30 may be made as a common internal wiring, and the same wiring may be done for SW2 of the electrical equipment 50 (50-1) and SW4 of the electromechanical equipment 50 (50-2).

[0145] Furthermore, even in the fourth embodiment, the determination unit 60 may also be configured to connect the internal wiring from each normally closed switch to the terminal block 30 for connecting to the external common line 108 as separate internal wirings, and then connect them to the external common line 108. By applying other embodiments of the determination unit shown in the third embodiment, the determination unit can perform a determination process similar to the determination process shown in Figure 7, thereby determining whether the electrical equipment is operating or the external common line is disconnected. Additionally, other embodiments of the determination unit in the fourth embodiment are basically the same as other embodiments of the determination unit shown in the third embodiment, but the resulting third wiring circuit will be different.

[0146] [f. Specific implementations of tunnel emergency equipment using a wire break monitoring system] A specific embodiment of a wire break monitoring system for tunnel emergency equipment, in which multiple fire hydrant devices are connected to the disaster prevention receiving panel shown in Figure 1, will be described in more detail below.

[0147] In Figure 1, the tunnel emergency equipment consists of a disaster prevention receiving panel that functions as a higher-level device, to which four fire hydrant devices that function as terminal devices are connected in stages. Since the wiring to the transmitter 24, pump start push button 32, and pump start interlocking device 34, which are electrical devices located on the terminal devices, are subject to wire break monitoring, the fourth embodiment of the wire break monitoring system will be applied.

[0148] Furthermore, the explanation will be given with reference to Figure 16, which shows the wiring circuit diagram of the first stage fire hydrant device 10 (10-1); Figure 17, which shows the wiring circuit diagram of the final stage fire hydrant device 10 (10-4); and Figure 18, which shows the wiring circuit diagrams for the transmitter 24, pump start push button 32, and pump start interlocking device 34 in the first and final stage fire hydrant devices shown in Figures 16 and 17.

[0149] (f1. Wiring circuit for the first stage fire hydrant system) The wiring circuit of the first stage fire hydrant device 10(10-1) will be explained in more detail. As shown in Figure 16, the first stage fire hydrant device 10(10-1) is equipped with electrical equipment including a telephone jack 28, a transmitter 24, an answer lamp 26, a pump start push button 32, and a pump start interlocking device 34. Of these, the wiring circuit that passes through the electrical equipment monitored by the wire break monitoring system is the wiring circuit that passes through the transmitter 24, the pump start push button 32, and the pump start interlocking device 34.

[0150] Here, the switches provided on the transmitter 24 are shown as the first normally closed switch SW1 and the second normally closed switch SW2 of the electrical equipment 50 (50-1) in Figure 13, which shows the fourth embodiment of the wire break monitoring system.

[0151] Furthermore, the switches provided on the pump start push button 32 are shown as the first normally closed switch SW3 and the second normally closed switch SW4 of the electrical equipment 50 (50-2) in Figure 13. Also, since the switches of the pump start interlocking device 34 are switches that are interlocked with the switches on the pump start push button 32, they are shown as the first normally closed switch SW5 connected in parallel to the first normally closed switch SW3, and the second normally closed switch SW6 connected in parallel to the second normally closed switch SW4.

[0152] In the wiring circuit forming the loop line for wire break monitoring, the first normally closed switches SW3 and SW5 of the pump start push button 32 and pump start interlocking device 34, which are connected in parallel in this manner, are treated as a single switch, and the second normally closed switches SW4 and SW6 are similarly treated as a single switch.

[0153] Furthermore, the transmitter 24 is equipped with a normally open switch SW7 that is linked to the operation of the push button. Therefore, the switch on the transmitter 24 is a 3-circuit switch, with two of the circuits being normally closed contacts (b-contacts) and the remaining circuit being a normally open contact (a-contact).

[0154] Furthermore, the fire hydrant device 10 (10-1) is equipped with a terminal block 30. The terminal block 30 has terminals pre-assigned to each electrical device, for example, 32 terminals in total. Terminals A1 to A16 are assigned to the transmitter 24, pump start push button 32, and pump start interlocking device 34, which are included in the wiring circuit subject to wire break monitoring, using the same reference numerals as in Figure 13.

[0155] From the disaster prevention receiver panel 12, the first manual notification line M1, the second manual notification line M2, the manual notification common line MC, the first pump start line HA1, the second pump start line HA1, the response line MF, the response common line FC, the telephone line T, and the telephone common line TC are drawn out and connected to the terminal block 30. Here, the first manual notification line M1 and the second manual notification line M2 correspond to the first external signal line 104 and the second external signal line 106 in Figure 13, the first pump start line HA1 and the second pump start line HA2 correspond to the first external signal line 114 and the second external signal line 116 in Figure 13, and the manual notification common line MC corresponds to the external common line 108 in Figure 13.

[0156] Furthermore, the disaster prevention receiver panel 12 is equipped with a determination unit 60, from which the first manual notification line M1, the second manual notification line M2, the manual notification common line MC, the first pump start line HA1, and the second pump start line HA2 are drawn.

[0157] The determination unit 60 detects the first wiring current i11 of the first wiring circuit, which is formed in a loop shape via the first normally closed switch SW1 of the transmitter 24 installed in the fire hydrant devices 10(10-1) to 10(10-4), and includes the first manual alarm line M1 and the manual alarm common line MC. The determination unit 60 also detects the second wiring current i12 of the second wiring circuit, which is formed in a loop shape via the second normally closed switch SW2 of the transmitter 24 installed in the fire hydrant devices 10(10-1) to 10(10-4), and includes the second manual alarm line M2 and the manual alarm common line MC.

[0158] The determination unit 60 then performs a determination process similar to the determination process shown in Figure 4, and determines whether normal monitoring (the normal state in the tunnel emergency equipment where the transmitter 24 is not activated), activation of the transmitter 24 installed in the fire hydrant devices 10(10-1) to 10(10-4), a break in the first wiring circuit to the transmitter 24, or a break in the second wiring circuit.

[0159] Furthermore, the determination unit 60 detects the first wiring current i21 of the first wiring circuit, which includes the first pump start line HA1 and the manual notification common line MC, and is formed in a loop via the first normally closed switches SW3 and SW5, which are connected in parallel to the pump start push button 32 and the pump start interlocking device 34, which are provided on the fire hydrant devices 10(10-1) to 10(10-4). Furthermore, the determination unit 60 detects the second wiring current i22 of the second wiring circuit, which includes the second pump start line HA2 and the manual notification common line MC, and is formed in a loop via the second normally closed switches SW4 and SW6, which are connected in parallel to the pump start push button 32 and the pump start interlocking device 34, which are provided on the fire hydrant devices 10(10-1) to 10(10-4).

[0160] The determination unit 60 then performs a determination process similar to the determination process shown in Figure 4, and determines whether normal monitoring is performed (the normal state in the tunnel emergency equipment where the pump start push button 32 and the pump start interlocking device 34 are not in operation), whether the pump start push button 32 and the pump start interlocking device 34 provided on the fire hydrant devices 10(10-1) to 10(10-4) are in operation, whether there is a break in the first wiring circuit and whether there is a break in the second wiring circuit for the pump start push button 32 and the pump start interlocking device 34.

[0161] Furthermore, the fire hydrant system has unique wiring circuits that are not present in the disconnection monitoring system shown in Figure 13, namely the wiring circuits for the response lamp 26 and the telephone jack 28. The wiring circuit for the response lamp 26 is [response line MF]-[terminal block 30]-[response lamp 26]-[switch SW7 of transmitter 24]-[terminal block 30]-[response common line FC], and the response lamp 26 lights up in response to a response signal from the disaster prevention receiving panel 12, provided that switch SW7 is closed in conjunction with the push button operation of transmitter 24. The response line MF is connected to the response line MF of the next fire hydrant system 10 (10-2) via terminal block 30. Similarly, the response common line FC is connected to the response common line FC of the next fire hydrant system 10 (10-2) via terminal block 30.

[0162] The wiring circuit for the telephone jack 28 is [telephone line T]-[terminals T1, T2]-[telephone jack 28]-[terminals TC2, TC1]-[telephone common line TC]. When the plug of the handset carried by the user is connected to the telephone jack 28, a call current flows and a call is initiated at the disaster prevention receiving panel 12. The call connection is established when the handset on the disaster prevention receiving panel 12 side is picked up. The telephone line T is also connected to the telephone line T of the next stage fire hydrant device 10 (10-2) via terminal block 30. Similarly, the telephone common line TC is also connected to the telephone common line TC of the next stage fire hydrant device 10 (10-2) via terminal block 30.

[0163] (f2. Wiring circuit for the final stage fire hydrant system) The wiring circuit of the final stage fire hydrant device 10(10-4) will now be explained. As shown in Figure 17, the final stage fire hydrant device 10(10-4) has basically the same electrical equipment and wiring configuration as the first stage fire hydrant device 10(10-1) shown in Figure 16. The differences are that, since there is no next stage fire hydrant device, the external wiring from the terminal block 30 to the next stage is omitted, and the wiring circuits for the transmitter 24, pump start push button 32, and pump start interlocking device 34 use the wiring configuration of the terminal device 100(100-2) in Figure 13. Therefore, the same reference numerals as in Figure 16 will be used, and their explanation will be omitted.

[0164] (f3. Wiring circuits monitored for disconnection) In a tunnel emergency system in which the first-stage fire hydrant device 10(10-1) in Figure 16 to the final-stage fire hydrant device 10(10-4) in Figure 17 are connected in stages to the disaster prevention receiving panel 12, the wiring circuit formed by the determination unit 60 of the disaster prevention receiving panel 12 to determine normal monitoring, the operation of the transmitter 24, the pump start push button 32 and the pump start interlocking device 34, and the disconnection of wiring will be explained in more detail with reference to Figure 18.

[0165] In Figure 18, the path of the first wiring circuit, which includes the first manual notification line M1 and the manual notification common line MC and forms a loop line passing through the first normally closed switch SW1 and the first termination resistor 36 of the transmitter 24 installed in the fire hydrant devices (10-1) to 10(10-4), is indicated by the following symbols: [Terminal A of the disaster prevention receiving panel 12]-[First manual notification line M1]-[Terminal A1 of the terminal block 30 of the fire hydrant device 10(10-1)]-[Terminal A2 of the terminal block 30 of the fire hydrant device 10(10-1)]-[First internal wiring]-[First normally closed switch SW1 of the transmitter 24 of the fire hydrant device 10(10- 1) Terminal A8 of terminal block 30 of fire hydrant device 10 (10-1) - Terminal A7 of terminal block 30 of fire hydrant device 10 (10-1) - First manual alarm line M1 - (omitted) - Terminal A1 of terminal block 30 of fire hydrant device 10 (10-4) - First termination resistor 36 - Terminal A2 of terminal block 30 of fire hydrant device 10 (10-4) - First internal wiring - First normally closed switch SW1 of transmitter 24 of fire hydrant device 10 (10-4) - First internal wiring - Terminal A8 of terminal block 30 of fire hydrant device 10 (10-4) - Terminal A7 of terminal block 30 of fire hydrant device 10 (10-4) - Manual alarm common line MC - Terminal E of disaster prevention receiver panel 12. Note that (omitted) refers to parts of the fire hydrant devices 10(10-2) and 10(10-3) that are not shown in the diagram.

[0166] Furthermore, in Figure 18, the path of the second wiring circuit, which includes the second manual notification line M2 and the manual notification common line MC and forms a loop line passing through the second normally closed switch SW2 and the second termination resistor 38 of the transmitter 24 installed in the fire hydrant devices 10(10-1) to 10(10-4), is indicated by the following symbols: [Terminal B of the disaster prevention receiving panel 12]-[Second manual notification line M2]-[Terminal A3 of the terminal block 30 of the fire hydrant device 10(10-1)]-[Terminal A4 of the terminal block 30 of the fire hydrant device 10(10-1)]-[First internal wiring]-[Second normally closed switch SW2 of the transmitter 24 of the fire hydrant device 10(10-1)]-[First internal wiring]-[Fire hydrant device 10( [Terminal A6 of terminal block 30 of 10-1] - [Terminal A5 of terminal block 30 of fire hydrant device 10 (10-1)] - [Second manual alarm line M2] - (omitted) - [Terminal A3 of terminal block 30 of fire hydrant device 10 (10-4)] - [Second termination resistor 38] - [Terminal A4 of terminal block 30 of fire hydrant device 10 (10-4)] - [First internal wiring] - [Second normally closed switch SW2 of transmitter 24 of fire hydrant device 10 (10-4)] - [First internal wiring] - [Terminal A8 of terminal block 30 of fire hydrant device 10 (10-4)] - [Terminal A7 of terminal block 30 of fire hydrant device 10 (10-4)] - [Manual alarm common line MC] - [Terminal E of disaster prevention receiver panel 12]. Note that (omitted) refers to parts of the fire hydrant devices 10(10-2) and 10(10-3) that are not shown in the diagram.

[0167] The determination unit 60 of the disaster prevention receiver panel 12 detects the first wiring current i11 and the second wiring current i12. If both the first wiring current i11 and the second wiring current i12 are "present", it determines that it is "normal monitoring". If neither the first wiring current i11 nor the second wiring current i12 is detected, and both the first wiring current i11 and the second wiring current i12 are "absent", it determines that the transmitter 24 is "operated", and for example outputs a fire alarm and applies a wiring voltage between the response line MF and the response common line to light up the response lamp 26.

[0168] Furthermore, the determination unit 60 determines that there is a "disconnection in the first wiring circuit" when the second wiring current i12 is detected and is in a "present" state, and when the first wiring current i11 is detected and is in a "present" state, and the second wiring current i12 is not detected and is in a "absent" state, and outputs a disconnection alarm, for example, by sound and display.

[0169] Furthermore, in Figure 18, the first wiring circuit, which includes the first pump activation line HA1 and the manual notification common line MC, and forms a loop line via the first normally closed switches SW3, SW5 and the first termination resistor 40 connected in parallel to the pump activation push button 32 and the pump activation interlocking device 34 provided on the fire hydrant devices 10(10-1) to 10(10-4), is indicated by the following symbols: [Terminal C of the disaster prevention receiving panel 12]-[First pump activation line HA1]-[Terminal A9 of the terminal block 30 of the fire hydrant device 10(10-1)]-[Terminal A10 of the terminal block 30 of the fire hydrant device 10(10-1)]-[First internal wiring]-[First normally closed switches SW3, SW5 connected in parallel to the pump activation push button 32 and the pump activation interlocking device 34 of the fire hydrant device 10(10-1)]-[First internal wiring [Wire]-[Terminal A16 of Terminal Block 30 of Fire Hydrant Device 10 (10-1)]-[Terminal A15 of Terminal Block 30 of Fire Hydrant Device 10 (10-1)]-[First Pump Start Line HA1]-(omitted)-[Terminal A9 of Terminal Block 30 of Fire Hydrant Device 10 (10-4)]-[First Termination Resistor 40]-[Terminal A10 of Terminal Block 30 of Fire Hydrant Device 10 (10-4)]-[First Internal Wiring]-[ The connection between the pump start push button 32 and the pump start interlocking device 34 of the fire hydrant device 10(10-4) is parallel to the first normally closed switches SW3 and SW5 - [first internal wiring] - [terminal A8 of the terminal block 30 of the fire hydrant device 10(10-4)] - [terminal A7 of the terminal block 30 of the fire hydrant device 10(10-4)] - [manual notification common wire MC] - [terminal E of the disaster prevention receiving panel 12]. Note that (omitted) represents parts of the fire hydrant devices 10(10-2) and 10(10-3) that are not shown in the diagram.

[0170] Furthermore, in Figure 18, the second wiring circuit, which includes the second pump activation line HA2 and the manual notification common line MC, and forms a loop line via the second normally closed switches SW4, SW6 and the second termination resistor 42 connected in parallel to the pump activation push button 32 and the pump activation interlocking device 34 installed on the fire hydrant devices 10(10-1) to 10(10-4), is indicated by the following symbols: [Terminal C of disaster prevention receiving panel 12]-[Second pump activation line HA2]-[Terminal A11 of terminal block 30 of fire hydrant device 10(10-1)]-[Terminal A12 of terminal block 30 of fire hydrant device 10(10-4)]-[Second internal wiring]-[Second normally closed switches SW4, SW6 connected in parallel to the pump activation push button 32 and the pump activation interlocking device 34 of fire hydrant device 10(10-1)]-[ [Second internal wiring] - [Terminal A14 of terminal block 30 of fire hydrant device 10 (10-1)] - [Terminal A13 of terminal block 30 of fire hydrant device 10 (10-1)] - [Second pump start line HA2] - (omitted) - [Terminal A11 of terminal block 30 of fire hydrant device 10 (10-4)] - [Second termination resistor 42] - [Terminal A12 of terminal block 30 of fire hydrant device 10 (10-4)] - [Fire extinguishing The connection between the pump start push button 32 of the valve device 10(10-4) and the pump start interlocking device 34 is as follows: Second normally closed switch SW4, SW6 - [Second internal wiring] - [Terminal A8 of the terminal block 30 of the fire hydrant device 10(10-4)] - [Terminal A7 of the terminal block 30 of the fire hydrant device 10(10-4)] - [Manual notification common wire MC] - [Terminal E of the disaster prevention receiving panel 12]. Note that (omitted) represents parts of the fire hydrant devices 10(10-2) and 10(10-3) that are not shown in the diagram.

[0171] The determination unit 60 of the disaster prevention receiving panel 12 detects the first wiring current i21 and the second wiring current i22. If both the first wiring current i21 and the second wiring current i22 are "present", it determines "normal monitoring". If neither the first wiring current i21 nor the second wiring current i22 is detected, and both the first wiring current i21 and the second wiring current i22 are "absent", it determines "operation of the pump start button 32 and the pump start interlocking device 34", and starts the pump operation of, for example, the fire pump equipment.

[0172] Furthermore, the determination unit 60 determines that there is a "disconnection in the first wiring circuit" when the second wiring current i22 is detected and is in a "present" state, and when the first wiring current i21 is detected and is in a "present" state, and the second wiring current i22 is not detected and is in a "disconnection in the second wiring circuit" state, and outputs a disconnection alarm, for example, by sound and display.

[0173] Furthermore, even in the specific embodiment of the tunnel emergency equipment, the fourth embodiment of the wire break monitoring system is applicable. Therefore, the determination unit 60 provided in the disaster prevention receiving panel 12 may be modified to apply another embodiment of the determination unit to perform a determination process similar to the determination process shown in Figure 7, thereby enabling determination of whether it is "operation of electrical equipment" or "disconnection of an external common wire."

[0174] In the determination unit 60 of this embodiment, if the first wiring current i11 of the first wiring circuit and the second wiring current i12 of the second wiring circuit connected to the transmitter 24 are not detected, and both the first wiring current i11 and the second wiring current i12 are "none", the determination unit does not determine that "the transmitter 24 is operating". Instead, as shown in Figures 18 and 19, the terminal B of the disaster prevention receiver panel 12 to which the second manual notification line M2 is connected is switched from a terminal with (+) polarity for applying a wiring voltage between the second manual notification line M2 and the manual notification common line MC to a terminal with (-) polarity for applying a wiring voltage between the first manual notification line M1 and the second manual notification line M2. Based on the state of the third wiring current i13 flowing through the third wiring circuit that forms a loop line including the first manual notification line M1 and the second manual notification line M2, the determination unit 60 further determines whether "the transmitter 24 is operating" or "the manual notification common line MC is disconnected".

[0175] Furthermore, if the first wiring current i21 of the first wiring circuit and the second wiring current i22 of the second wiring circuit for the pump start push button 32 and the pump start interlocking device 34 are not detected, and both the first wiring current i21 and the second wiring current i22 are "none", then it is not determined that the pump start push button 32 and the pump start interlocking device 34 are "operated". Instead, as shown in Figures 18 and 19, terminal D of the disaster prevention receiver panel 12 to which the second pump start line HA2 is connected is switched from a terminal with (+) polarity for applying a wiring voltage between the second pump start line HA2 and the manual notification common line MC to a terminal with (-) polarity for applying a wiring voltage between the first pump start line HA1 and the second pump start line HA2. Based on the state of the third wiring current i23 flowing through the third wiring circuit that forms a loop line including the first pump start line HA1 and the second pump start line HA2, a further determination is made as to whether the pump start push button 32 and the pump start interlocking device 34 are "operated" or whether the external common line is "disconnected".

[0176] Thus, when the transmitter 24 is activated and the first normally closed switch SW1 and the second normally closed switch SW2 are open, the path to the third wiring circuit is interrupted by the first normally closed switch SW1 and the second normally closed switch SW2 of the electrical equipment transmitter 24, which is open, so the third wiring current i13 does not flow.

[0177] Furthermore, the third wiring circuit, formed by switching the voltage polarity of terminal D to which the second pump start line HA2 is connected from (+) to (-), will not allow the third wiring current i23 to flow when the pump start push button 32 and pump start interlocking device 34 are activated and the first normally closed switch SW3 and second normally closed switch SW4 or the first normally closed switch SW5 and second normally closed switch SW6 are opened, because the path is interrupted by the first normally closed switches SW3, SW5 and the second normally closed switches SW4, SW6 of the pump start push button 32 and pump start interlocking device 34, which are open.

[0178] In contrast, if the manual notification common line MC is disconnected, the paths to the third wiring circuit for the transmitter 24 and the third wiring circuit for the pump start push button 32 and the pump start interlocking device 34 are not interrupted, forming a loop line. As a result, the third wiring current i13 flows from terminal A to terminal B of the disaster prevention receiving panel 12, and the third wiring current i23 flows from terminal C to terminal D of the disaster prevention receiving panel 12.

[0179] Therefore, after the determination unit 60 switches the voltage polarity of terminal B to which the second manual notification line M2 is connected from (+) to (-), if the third wiring current i13 is not detected and the value becomes "none", it determines that "the transmitter 24 is activated", and if the current i13 is detected and the value becomes "present", it determines that "the manual notification common line MC is broken".

[0180] Furthermore, after the determination unit 60 switches the voltage polarity of terminal D to which the second pump start line HA2 is connected from (+) to (-), if the third wiring current i23 is not detected and the value becomes "none", it determines that "the pump start push button 32 and the pump start interlocking device 34 are operating", and if current i13 is detected and the value becomes "present", it determines that "the manual notification common line MC is broken".

[0181] Therefore, the determination unit 60 of the disaster prevention receiver panel 12 can determine "disconnection of the manual notification common wire MC" separately from "operation of the transmitter 24" or "operation of the pump start push button 32 and pump start interlocking device 34," making it possible to avoid increasing the number of manual notification common wires MC and to eliminate the need for on-site confirmation by workers.

[0182] In this embodiment, the determination unit 60 switches the voltage polarity of terminal B to which the second manual notification line M2 is connected from (+) to (-). However, the voltage polarity of terminal A to which the first manual notification line M1 is connected may also be switched from (+) to (-), and the state of the third wiring current i13 flowing from terminal B to terminal A may be used to determine whether "the transmitter 24 is activated" or "the manual notification common line MC is disconnected".

[0183] Furthermore, although the determination unit 60 was configured to switch the voltage polarity of terminal D to which the second pump start line HA2 is connected from (+) to (-), it may also be configured to switch the voltage polarity of terminal C to which the first pump start line HA1 is connected from (+) to (-), and determine whether "the pump start push button 32 and the pump start interlocking device 34 are activated" or "the manual notification common wire MC is disconnected" based on the state of the third wiring current i23 flowing from terminal D to terminal C.

[0184] [g. Variations of the present invention] Modifications of the wire break monitoring system and tunnel emergency equipment according to the present invention will be described in more detail. In addition to the embodiments described above, the wire break monitoring system and tunnel emergency equipment of the present invention include the following modifications.

[0185] (Manual notification device) The above embodiment uses a fire hydrant system as an example of a terminal device for tunnel emergency equipment, but the emergency equipment device that functions as a terminal device is arbitrary and may be, for example, a manual notification device connected to a disaster prevention receiving panel. The manual notification device is equipped with a transmitter, and by forming the wiring circuit via its switch into a loop shape, similar to the case of the fire hydrant system, it is possible to monitor for disconnections in the wiring circuit, including the internal wiring of the manual notification device.

[0186] (Number and types of terminal devices and electrical equipment) The number and types of terminal devices, fire hydrant devices functioning as terminal devices, and electrical equipment corresponding to the wiring to be monitored for disconnections, as shown in the above embodiment, are merely examples and are not limited thereto. A disconnection monitoring system can be configured with any number and type of equipment, and disconnection monitoring can be performed by forming the wiring circuit to be monitored for disconnections as a loop line.

[0187] (others) Furthermore, the present invention includes appropriate modifications that do not impair its purpose and advantages, and is not limited by the numerical values ​​shown in the above embodiments. [Explanation of symbols]

[0188] 10(10-1)~10(10-4): Fire hydrant system 10a, 10b: Enclosure 11a, 11b: Decorative frame 12: Disaster Prevention Receiving Panel 14: Wiring Cables 15: Fire hydrant door 16: Maintenance Door 18: Fire extinguisher door 20: Electric Door 22: Red indicator light 24: Transmitter 25a, 25b: Terminal box 26: Response lamp 28: Phone hijacking 30:Terminal block 32: Pump start push button 34: Pump startup interlocking device 36, 40: 1st termination resistor 38, 42: Second terminating resistor 46, 48: Termination resistors 50, 50(50-1), 50(50-2): Electrical equipment 60: Judgment section 100, 100(100-1), 100(100-2): Terminal device 102: Higher-level device 104, 114: First external signal line 106, 116: Second external signal line 108, 108-1, 108-2: External common lines A1~A16: Terminals SW1, SW3, SW5: First normally closed switch SW2, SW4, SW6: Second normally closed switch M1: 1st manual report line M2: 2nd manual report line MC: Manual notification common line HA1: First pump starting line HA2: Second pump starting line MF: Response line FC: Response Common Line T:Telephone line TC: Telephone Common Line

Claims

1. A disconnection monitoring system for equipment in which electrical devices are connected to a higher-level device, The aforementioned electrical equipment includes a first normally closed switch and a second normally closed switch that are opened in conjunction with a predetermined operation. The aforementioned higher-level device is The first wiring current flows through the first wiring circuit, which is connected in a loop from the above-level device via the first normally closed switch and the first terminator to the above-level device, The second wiring current flows through the second wiring circuit, which is connected in a loop from the aforementioned higher-level device via the second normally closed switch and the second terminator to the aforementioned higher-level device, Based on, A wire break monitoring system characterized by determining whether the electrical equipment is inoperable, whether the electrical equipment is operational, whether the first wiring circuit is broken, and whether the second wiring circuit is broken.

2. A wire breakage monitoring system according to claim 1, The aforementioned electrical equipment is placed in a terminal device equipped with a terminal block. The first wiring circuit consists of a first external signal line from the host device to the terminal block, a first internal wiring line from the terminal block to the terminal block via the first normally closed switch and the first terminator, and a first external common line from the terminal block to the host device. The disconnection monitoring system is characterized in that the second wiring circuit comprises a second external signal line from the higher-level device to the terminal block, a second internal wiring from the terminal block to the terminal block via the second normally closed switch and the second terminator, and a second external common line from the terminal block to the higher-level device.

3. A wire breakage monitoring system according to claim 2, A wire breakage monitoring system characterized in that the first external common wire and the second external common wire are used as a common external common wire.

4. A wire breakage monitoring system according to claim 3, A wire breakage monitoring system characterized in that a portion of the first internal wiring from the first normally closed switch on the common external common line side to the terminal block and a portion of the second internal wiring from the second normally closed switch on the common external common line side to the terminal block are made common, and the terminal block is connected by the common internal wiring.

5. A wire breakage monitoring system according to any one of claims 1 to 4, The aforementioned higher-level device is If the first wiring current and the second wiring current are detected, it is determined that the electrical equipment is not operating. If neither the first wiring current nor the second wiring current is detected, it is determined that the electrical equipment is operating. If the first wiring current is not detected and the second wiring current is detected, it is determined that the first wiring circuit is open. A wire break monitoring system characterized in that, if the first wiring current is detected and the second wiring current is not detected, it is determined that the second wiring circuit is broken.

6. A wire breakage monitoring system according to claim 3, The aforementioned higher-level device is If the first wiring current and the second wiring current are detected, it is determined that the electrical equipment is not operating. If the first wiring current is not detected and the second wiring current is detected, it is determined that the first wiring circuit is open. If the first wiring current is detected and the second wiring current is not detected, it is determined that the second wiring circuit is open. If the first wiring current and the second wiring current are not detected, a determination is further made based on the third wiring current flowing through a third wiring circuit that is connected in a loop from the higher-level device to the higher-level device via the first external signal line, the first internal wiring, the second internal wiring, and the second external signal line. If the third wiring current is detected, it is determined that the external common wire is broken. A wire breakage monitoring system characterized in that, if the third wiring current is not detected, it is determined that the electrical equipment is operating.

7. A wire breakage monitoring system according to claim 1, There are multiple such electrical devices. The first wiring circuit is connected in a loop from the higher-level device through the first normally closed switches and first terminators of all the electrical equipment to the higher-level device. The disconnection monitoring system is characterized in that the second wiring circuit is connected in a loop from the higher-level device to the higher-level device via the second normally closed switch and the second terminator of all the electrical equipment.

8. A wire breakage monitoring system according to claim 1, There are multiple such electrical devices. The first terminator and the second terminator are provided for each electrical device. Multiple first wiring circuits are formed for each electrical device, by connecting in a loop from the higher-level device to the higher-level device via the first normally closed switch and first terminator of the electrical device. Multiple second wiring circuits are formed for each electrical device, by connecting them in a loop from the higher-level device to the higher-level device via the second normally closed switch and second terminator of the electrical device. A wire break monitoring system characterized in that the higher-level device determines whether each electrical device is inoperable, whether each electrical device is operational, whether each first wiring circuit is open, and whether each second wiring circuit is open, based on the first wiring current flowing through the first wiring circuit and the second wiring current flowing through the second wiring circuit for each electrical device.

9. A wire breakage monitoring system according to claim 1, The aforementioned electrical equipment is divided into predetermined groups and exists in multiple quantities. The first terminator and the second terminator are provided for each predetermined group, Multiple first wiring circuits are formed for each predetermined group, by connecting in a loop from the higher-level device to the higher-level device via all the first normally closed switches and first terminators of the electrical equipment belonging to the predetermined group. Multiple second wiring circuits are formed for each predetermined group, by connecting in a loop from the higher-level device to the higher-level device via all the second normally closed switches and second terminators of the electrical equipment belonging to the predetermined group. A wire break monitoring system characterized in that the higher-level device determines, based on the first wiring current flowing through the first wiring circuit and the second wiring current flowing through the second wiring circuit for each predetermined group, whether the electrical equipment belonging to each group is inoperable, whether the electrical equipment belonging to each group is operational, whether the first wiring circuit is open, and whether the second wiring circuit is open.

10. A wire breakage monitoring system according to claim 1, The aforementioned equipment is an emergency tunnel system in which electrical equipment located in a fire hydrant system or manual notification system is connected to a disaster prevention receiving panel that functions as a higher-level device. The aforementioned electrical equipment is characterized by including a transmitter, a pump start push button, and a pump start interlocking device, and is a wire breakage monitoring system.

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