A communication cabinet environment monitoring system

Abstract

The utility model discloses a kind of communication cabinet environment monitoring systems, belong to communication cabinet monitoring technical field, solve due to the rear part hot air of cabinet is not fully discharged, partial hot air is inhaled by equipment air inlet again, form difficult to detect microscopic thermal cycle, simultaneously, the idle installation position of high-power equipment adjacent is not installed blind plate, leading to hot air short circuit to front cold channel, in addition, the fan inside equipment is slightly aging or dust accumulation, air volume quietly reduces and has no alarm problem. Including sensing bridge circuit, differential amplifier circuit, window comparator circuit and delay lock and output circuit, the detection end of sensing bridge circuit is used to set at the lower cold air inlet of communication cabinet. The utility model compares the temperature difference of lower cold air inlet in communication cabinet and the side of electric appliance in communication cabinet by continuously, automatically triggers and locks alarm state when detecting abnormal local overheating, until manual reset, to realize remote overheating fault indication.

Description

Technical Field

[0001] This utility model relates to the field of communication cabinet monitoring technology, and in particular to a communication cabinet environment monitoring system. Background Technology

[0002] A communication cabinet is a specialized enclosure used to house communication equipment. It is typically made of high-quality steel, providing excellent load-bearing capacity and electromagnetic shielding. Its internal structure is rationally designed to house various communication modules and devices. The cabinet is equipped with ventilation holes and cooling fans to ensure effective heat dissipation and maintain a stable temperature environment during operation.

[0003] During the use of communication cabinets, hot air at the rear of the cabinet is not fully exhausted, and some hot air is re-drawn in through the equipment air inlets, creating a subtle micro-thermal circulation. Simultaneously, the lack of blind flanges in adjacent unused mounting positions for high-power equipment causes hot air to short-circuit to the front cold aisle. These factors result in certain equipment, especially those located in the lower part of the cabinet, having air inlet temperatures far exceeding the monitoring readings for the server room environment, creating localized overheating problems that are difficult to detect through macroscopic monitoring.

[0004] Therefore, a communication cabinet environment monitoring system is proposed to solve or alleviate the above problems. Utility Model Content

[0005] The purpose of this utility model is to address the shortcomings of existing technologies by proposing a communication cabinet environment monitoring system.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A communication cabinet environmental monitoring system includes a sensing bridge circuit, a differential amplifier circuit, a window comparator circuit, and a delay lockout and output circuit. The sensing bridge circuit's detection terminals are located at the lower cold air inlet of the communication cabinet and on the side of the electrical appliances inside the cabinet. The output terminal of the sensing bridge circuit is connected to the input terminal of the differential amplifier circuit, the output terminal of the differential amplifier circuit is connected to the input terminal of the window comparator circuit, and the output terminal of the window comparator circuit is connected to the input terminal of the delay lockout and output circuit. An alarm indicator light is connected to the output terminal of the delay lockout and output circuit. The sensing bridge circuit includes a first NTC thermistor, a second NTC thermistor, a first resistor, and a second resistor. The first terminal of the first NTC thermistor is set as the first output terminal of the sensing bridge circuit, and the second terminal of the first NTC thermistor is grounded. The first terminal of the first resistor is energized and connected to the first terminal of the first NTC thermistor. The first terminal of the second NTC thermistor is set as the second output terminal of the sensing bridge circuit, and the second terminal of the second NTC thermistor is grounded. The first terminal of the second resistor is connected to the first terminal of the first NTC thermistor. The first NTC thermistor is connected to the first terminal of the second resistor. The first NTC thermistor is installed at the lower cold air inlet of the communication cabinet, and the second NTC thermistor is installed on the electrical side inside the communication cabinet. The window comparison circuit includes a first LM393 voltage comparator, a TL431 reference voltage source, a first adjustable resistor, and a pull-up resistor. The cathode of the TL431 reference voltage source is connected to the power supply, the anode of the TL431 reference voltage source is grounded, and the reference electrode and cathode of the TL431 reference voltage source are connected together. The first terminal of the first adjustable resistor is connected to the cathode of the TL431 reference voltage source. The second terminal of the first adjustable resistor serves as the sliding arm terminal, and the third terminal of the first adjustable resistor is grounded. The inverting input terminal of the first LM393 voltage comparator is connected to the sliding arm terminal of the first adjustable resistor. The non-inverting input terminal of the first LM393 voltage comparator serves as the input terminal of the window comparison circuit. The output terminal of the first LM393 voltage comparator is set as the output terminal of the window comparison circuit. The pull-up resistor is connected between the output terminal of the first LM393 voltage comparator and the power supply.The delay-locked-out and output circuit includes an NE555 monostable multivibrator, a CD4081 AND gate, a transistor, a relay, a manual reset switch, and a freewheeling diode. The trigger terminal of the NE555 monostable multivibrator is connected to the output terminal of the window comparator circuit through a delay resistor. The threshold and discharge terminals of the NE555 monostable multivibrator are both connected to its trigger terminal. The output terminal of the NE555 monostable multivibrator is grounded through a delay capacitor. The reset and power supply terminals of the NE555 monostable multivibrator are both energized. The first... The input terminal is connected to the output terminal of the NE555 monostable multivibrator. The second input terminal of the CD4081 AND gate is connected to the first terminal of the manual reset switch, and the second terminal of the manual reset switch is energized. The output terminal of the CD4081 AND gate is connected to the base of the transistor through a base resistor. The emitter of the transistor is grounded. The collector of the transistor is connected to the first terminal of the relay coil and the anode of the freewheeling diode. The second terminal of the relay coil and the cathode of the freewheeling diode are both energized. The normally open contact of the relay is connected in the energizing circuit of the alarm indicator light.

[0007] Preferably, the differential amplifier circuit includes a first OP2177 operational amplifier, a third resistor, a fourth resistor, a fifth resistor, and a sixth resistor. The non-inverting input of the first OP2177 operational amplifier is connected to the first output of the sensing bridge circuit through the third resistor. The non-inverting input of the first OP2177 operational amplifier is grounded through the fourth resistor. The inverting input of the first OP2177 operational amplifier is connected to the second output of the sensing bridge circuit through the fifth resistor. The sixth resistor is connected between the inverting input and the output of the first OP2177 operational amplifier. The output of the first OP2177 operational amplifier is set as the output of the differential amplifier circuit.

[0008] Preferably, the resistance values ​​of the third resistor, the fourth resistor, the fifth resistor, and the sixth resistor are set to be equal.

[0009] This utility model has the following beneficial effects: This invention achieves remote overheating fault indication by continuously comparing the temperature difference between the lower cold air inlet inside the communication cabinet and the electrical components inside the cabinet. When abnormal local overheating is detected, the alarm is automatically triggered and locked until manual reset. Attached Figure Description

[0010] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a structural block diagram of the present invention.

[0012] In the diagram: 1. Sensor bridge circuit; 2. Differential amplifier circuit; 3. Window comparator circuit; 4. Delay lockout and output circuit; 5. Alarm indicator light. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0014] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0015] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0016] In the description of this utility model, it should be understood that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used to facilitate the description of this utility model and to simplify the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0017] Furthermore, the terms "first," "second," and "third" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0018] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0019] A communication cabinet environment monitoring system, such as Figure 1 As shown, the system includes a sensing bridge circuit 1, a differential amplifier circuit 2, a window comparator circuit, and a delay lockout and output circuit 4. The detection terminal of the sensing bridge circuit 1 is used to be installed at the lower cold air inlet of the communication cabinet and on the side of the electrical appliances inside the communication cabinet. The output terminal of the sensing bridge circuit 1 is connected to the input terminal of the differential amplifier circuit 2. The output terminal of the differential amplifier circuit 2 is connected to the input terminal of the window comparator circuit 3. The output terminal of the window comparator circuit is connected to the input terminal of the delay lockout and output circuit 4. An alarm indicator light 5 is connected to the output terminal of the delay lockout and output circuit 4.

[0020] The sensing bridge circuit 1 includes a first NTC thermistor, a second NTC thermistor, a first resistor, and a second resistor. The first terminal of the first NTC thermistor is set as the first output terminal of the sensing bridge circuit 1, the second terminal of the first NTC thermistor is grounded, the first terminal of the first resistor is energized, and the second terminal of the first resistor is connected to the first terminal of the first NTC thermistor. The first terminal of the second NTC thermistor is set as the second output terminal of the sensing bridge circuit 1, the second terminal of the second NTC thermistor is grounded, the first terminal of the second resistor is energized, and the second terminal of the second resistor is connected to the first terminal of the second NTC thermistor.

[0021] The differential amplifier circuit 2 includes a first OP2177 operational amplifier, a third resistor, a fourth resistor, a fifth resistor, and a sixth resistor. The non-inverting input of the first OP2177 operational amplifier is connected to the first output of the sensing bridge circuit 1 through the third resistor. The non-inverting input of the first OP2177 operational amplifier is grounded through the fourth resistor. The inverting input of the first OP2177 operational amplifier is connected to the second output of the sensing bridge circuit 1 through the fifth resistor. The sixth resistor is connected between the inverting input and the output of the first OP2177 operational amplifier. The output of the first OP2177 operational amplifier is set as the output of the differential amplifier circuit 2.

[0022] The resistance values ​​of the third, fourth, fifth, and sixth resistors are set to be equal.

[0023] The window comparator circuit includes a first LM393 voltage comparator, a TL431 reference voltage source, a first adjustable resistor, and a pull-up resistor. The cathode of the TL431 reference voltage source is connected to power, the anode of the TL431 reference voltage source is grounded, and the reference terminal and cathode of the TL431 reference voltage source are connected together. The first terminal of the first adjustable resistor is connected to the cathode of the reference voltage source, the second terminal of the first adjustable resistor serves as the sliding arm terminal, and the third terminal of the first adjustable resistor is grounded. The inverting input terminal of the first LM393 voltage comparator is connected to the sliding arm terminal of the first adjustable resistor. The non-inverting input terminal of the first LM393 voltage comparator serves as the input terminal of the window comparator circuit 3. The output terminal of the first LM393 voltage comparator is set as the output terminal of the window comparator circuit 3. The pull-up resistor is connected between the output terminal of the first LM393 voltage comparator and the power supply.

[0024] The delay-lock and output circuit 4 includes an NE555 monostable multivibrator, a CD4081 AND gate, a transistor, a relay, a manual reset switch, and a freewheeling diode. The trigger terminal of the NE555 monostable multivibrator is connected to the output terminal of the window comparator circuit 3 through a delay resistor. The threshold and discharge terminals of the NE555 monostable multivibrator are both connected to its trigger terminal. The output terminal of the NE555 monostable multivibrator is grounded through a delay capacitor. The reset and power supply terminals of the NE555 monostable multivibrator are both energized. The first input terminal of the CD4081 AND gate is connected to the output terminal of the NE555 monostable multivibrator. The second input terminal of the CD4081 AND gate is connected to the first terminal of the manual reset switch, and the second terminal of the manual reset switch is energized. The output terminal of the CD4081 AND gate is connected to the base of the transistor through a base resistor. The emitter of the transistor is grounded. The collector of the transistor is connected to the first terminal of the relay coil and the anode of the freewheeling diode. The second terminal of the relay coil and the cathode of the freewheeling diode are both energized. The normally open contact of the relay is connected in the energizing circuit of the alarm indicator 5.

[0025] When the communication cabinet environmental monitoring system is working, the sensing bridge circuit 1 continuously collects the key temperatures inside the communication cabinet. Specifically, this is achieved by installing a first NTC thermistor at the lower cold air inlet of the communication cabinet and a second NTC thermistor located on the side of the electrical appliances inside the communication cabinet. The resistance values ​​of these two negative temperature coefficient thermistors change with the ambient temperature. They are connected to a voltage divider circuit with a fixed-value resistor and then to a stable power supply and ground, thereby converting the temperature change into a voltage signal. Specifically, a voltage signal representing the temperature at the lower cold air inlet of the communication cabinet is output from the midpoint between the first NTC thermistor and the resistor, and a voltage signal representing the temperature on the side of the electrical appliances inside the communication cabinet is output from the midpoint between the second NTC thermistor and the resistor. These two voltage signals are directly fed into the input terminal of the differential amplifier circuit 2.

[0026] The first OP2177 operational amplifier in the differential amplifier circuit 2 forms a subtractor circuit through four external resistors of completely equal value. This circuit calculates the voltage difference between two signals and amplifies it to an easily processed level. The non-inverting input of the first OP2177 operational amplifier receives the signal through a resistor and is grounded through a resistor to provide bias. The inverting input receives the signal through a resistor and is connected to the output through a resistor to form negative feedback and set the gain. The amplified voltage signal generated at its output is directly proportional to the actual temperature difference between the two monitoring points. This signal is sent to the window comparator circuit 3.

[0027] The window comparator circuit 3 determines whether the temperature difference exceeds the safety threshold. It is first provided with an extremely stable 2.5V reference voltage by a TL431 reference voltage source. This voltage is applied to a first adjustable resistor. By adjusting its slider, a threshold voltage corresponding to a specific allowable temperature difference can be set, such as 5 degrees Celsius. This voltage is sent to the inverting input of the first LM393 voltage comparator.

[0028] At the same time, a signal representing the actual temperature difference is sent to the non-inverting input of the first LM393 voltage comparator.

[0029] When the temperature on the electrical side of the communication cabinet rises abnormally due to microscopic thermal circulation, causing the signal voltage to exceed the set threshold, the output of the first LM393 voltage comparator will flip from high level to low level, thereby generating an effective alarm trigger signal.

[0030] This low-level signal then enters the delay-locked-out and output circuit 4. This circuit first filters the trigger signal to eliminate false alarms that may be caused by instantaneous temperature fluctuations. This signal is connected to the trigger terminal of the NE555 monostable multivibrator. Only when the low-level signal lasts for a sufficiently long time will the NE555 monostable multivibrator be reliably triggered. Its output terminal then jumps to a high level and enters a metastable state. This high-level signal is sent to the first input terminal of a CD4081 AND gate. The second input terminal of the CD4081 AND gate is connected to a manual reset button. In the normal state, the button keeps this input terminal at a high level, so the output terminal of the CD4081 AND gate also outputs a high level. This high level drives an NPN transistor to enter a saturated conduction state through a base resistor. The collector current of the transistor flows through the coil of the relay, causing it to close. The normally open contact of the relay closes, thereby energizing the remote alarm indicator 5 and emitting a continuous light alarm signal.

[0031] The above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A communication cabinet environment monitoring system, characterized in that, The system includes a sensing bridge circuit (1), a differential amplifier circuit (2), a window comparator circuit (3), and a delay lockout and output circuit (4). The detection terminal of the sensing bridge circuit (1) is used to be installed at the lower cold air inlet of the communication cabinet and on the side of the electrical appliances inside the communication cabinet. The output terminal of the sensing bridge circuit (1) is connected to the input terminal of the differential amplifier circuit (2), the output terminal of the differential amplifier circuit (2) is connected to the input terminal of the window comparator circuit (3), and the output terminal of the window comparator circuit (3) is connected to the input terminal of the delay lockout and output circuit (4). (4) The output terminal is connected to an alarm indicator light (5); the sensing bridge circuit (1) includes a first NTC thermistor, a second NTC thermistor, a first resistor, and a second resistor. The first terminal of the first NTC thermistor is set as the first output terminal of the sensing bridge circuit (1), the second terminal of the first NTC thermistor is grounded, the first terminal of the first resistor is energized, and the second terminal of the first resistor is connected to the first terminal of the first NTC thermistor. The first terminal of the second NTC thermistor is set as the second output terminal of the sensing bridge circuit (1), and the second terminal of the second NTC thermistor is connected to the first terminal of the first NTC thermistor. The first end of the second resistor is grounded, the first end of the second resistor is energized, the second end of the second resistor is connected to the first end of the second NTC thermistor, the first NTC thermistor is used to be installed at the lower cold air inlet of the communication cabinet, and the second NTC thermistor is used to be installed on the electrical side inside the communication cabinet; the window comparison circuit (3) includes a first LM393 voltage comparator, a TL431 reference voltage source, a first adjustable resistor, and a pull-up resistor. The cathode of the TL431 reference voltage source is energized, the anode of the TL431 reference voltage source is grounded, and the reference electrode of the TL431 reference voltage source is grounded. The first adjustable resistor is connected to the cathode of the TL431 reference voltage source, the second adjustable resistor is used as the sliding arm terminal, the third adjustable resistor is grounded, the inverting input terminal of the first LM393 voltage comparator is connected to the sliding arm terminal of the first adjustable resistor, the non-inverting input terminal of the first LM393 voltage comparator is used as the input terminal of the window comparator circuit (3), the output terminal of the first LM393 voltage comparator is set as the output terminal of the window comparator circuit (3), and the pull-up resistor is connected between the output terminal of the first LM393 voltage comparator and the power supply.The delay-locked-out and output circuit (4) includes an NE555 monostable multivibrator, a CD4081 AND gate, a transistor, a relay, a manual reset switch, and a freewheeling diode. The trigger terminal of the NE555 monostable multivibrator is connected to the output terminal of the window comparator circuit (3) through a delay resistor. The threshold terminal and discharge terminal of the NE555 monostable multivibrator are both connected to its trigger terminal. The output terminal of the NE555 monostable multivibrator is grounded through a delay capacitor. The reset terminal and power supply terminal of the NE555 monostable multivibrator are both energized. The first step of the CD4081 AND gate... One input terminal is connected to the output terminal of the NE555 monostable multivibrator. The second input terminal of the CD4081 AND gate is connected to the first terminal of the manual reset switch. The second terminal of the manual reset switch is energized. The output terminal of the CD4081 AND gate is connected to the base of the transistor through a base resistor. The emitter of the transistor is grounded. The collector of the transistor is connected to the first terminal of the relay coil and the anode of the freewheeling diode. The second terminal of the relay coil and the cathode of the freewheeling diode are both energized. The normally open contact of the relay is connected in the energizing circuit of the alarm indicator (5).

2. The communication cabinet environment monitoring system according to claim 1, characterized in that, The differential amplifier circuit (2) includes a first OP2177 operational amplifier, a third resistor, a fourth resistor, a fifth resistor, and a sixth resistor. The non-inverting input terminal of the first OP2177 operational amplifier is connected to the first output terminal of the sensing bridge circuit (1) through the third resistor. The non-inverting input terminal of the first OP2177 operational amplifier is grounded through the fourth resistor. The inverting input terminal of the first OP2177 operational amplifier is connected to the second output terminal of the sensing bridge circuit (1) through the fifth resistor. The sixth resistor is connected between the inverting input terminal and the output terminal of the first OP2177 operational amplifier. The output terminal of the first OP2177 operational amplifier is set as the output terminal of the differential amplifier circuit (2).

3. The communication cabinet environment monitoring system according to claim 2, characterized in that, The resistance values ​​of the third, fourth, fifth, and sixth resistors are all set to be equal.

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