Electrical protection device and method for operating an electrical protection device

Abstract

The invention relates to an electrical protection device (30) comprising a power input (41), at least one power output (42, 43, 44) and a monitoring circuit (45) for monitoring an electrical parameter of the power output (42, 43, 44); wherein the monitoring circuit (45) is configured to activate a triggered state of the protection device (30) depending on the electrical parameter, in particular if the electrical parameter exceeds a threshold value, in which the power output (42, 43, 44) is electrically isolated from the power input (41); wherein a communication interface (46) is further provided, having at least one communication pin (pin 4); and a control unit (47) which is configured to reset the electrical protection device (30) in the triggered state of the protection device (30) depending on an electrical reset parameter on the communication pin of the communication interface (46), in particular depending of a voltage on the communication pin. The invention also relates to a method for operating an electrical protection device (30).

Description

[0001] Description

[0002] Electrical safety device and

[0003] Method for operating an electrical safety device

[0004] The invention relates to an electrical safety device having a power input, at least one power output and a monitoring circuit for monitoring an electrical parameter of the power output, and to a method for operating such an electrical safety device.

[0005] In particular, the invention relates to the field of power electronics, such as a device with electronic fuse for distributing electrical power in the field, i.e. in particular for field devices in the context of machines and systems, for example between automation components.

[0006] When supplying electrical power to devices, it is important to ensure that the current used does not exceed certain limits. This may be determined, for example, by the specifications of the devices used, which can be safely operated up to a maximum current, or general safety regulations may apply in certain areas of a device system that only permit certain currents.

[0007] To ensure that the supplied current does not exceed a certain value, electrical safety devices are typically used. These monitor the current and disconnect the devices from the power supply if a threshold is exceeded. Short-circuit detection can also be achieved.

[0008] The triggering of such a fuse leads to the temporary shutdown of one or more devices. Only when the fuse is reset do the connected devices receive electrical power again. Therefore, in many cases, it is desirable to minimize the time between the triggering of the fuse and its resetting in the event of a fault.

[0009] The electronic fuse is intended for decentralized use, particularly in the field. If the fuse blows, it must be acknowledged and thus reset to enable the connected devices to continue operating. For this purpose, the fuse can be connected to an IO-Link master, for example, to perform the acknowledgement remotely. The fuse can also be configured to acknowledge again after a certain cooling period. Furthermore, the fuse can be disconnected from the power supply by switching off the upstream power source.

[0010] Safety devices are known that can be controlled via a data connection. A reset signal can be transmitted to a safety device via this communication connection, which then automatically resets it. However, this integration of the safety device into a network is not possible in all applications.

[0011] Furthermore, many known devices are designed to automatically reset when they are disconnected from the power supply. However, this disconnection often entails the need to disconnect other electrical supply branches not affected by the current threshold being exceeded, and thus many additional devices. This should be avoided.

[0012] EP 1 950 784 B1 describes a reset device for an electrical safety device. It is provided that a reset movement is transmitted to the safety device by means of an actuator in order to reset it. An electromagnet is used for this purpose. DE 10 2019 213 604 A1 discloses a protective switching device for a low-voltage circuit. WO 2012 / 113 445 A2 describes a device for switching a power supply. WO 2018 / 185 051 A1 proposes an electrical switching device.

[0013] Other known solutions, for example, use Ethernet interfaces to control the reset, so that the security device must be integrated as a device into a communication network.

[0014] The known solutions have various disadvantages. Some require a mechanical button on the device housing to acknowledge the fuse. Furthermore, an external power supply is typically required to reset the fuse.

[0015] It is therefore the object of the invention to provide an electrical safety device and a method for operating an electrical safety device which enable simple and rapid resetting after the fuse has been triggered.

[0016] This object is achieved by a device of the type mentioned above having the features of the independent device claim and by a method having the features of the independent method claim. Advantageous embodiments and further developments of the invention are specified in the dependent claims.

[0017] The electrical safety device comprises a power input, at least one power output, and a monitoring circuit for monitoring an electrical parameter of the power output. The monitoring circuit is configured to activate a triggered state of the safety device depending on the electrical parameter, in particular when the electrical parameter exceeds a threshold value, in which the power output is electrically separated from the power input. A communication interface with at least one communication pin and a control unit are also provided. In this case, the control unit is configured to reset the electrical safety device in the triggered state of the safety device depending on an electrical reset parameter on the communication pin of the communication interface, in particular depending on a voltage on the communication pin.

[0018] In particular, the power input is designed for connection to a higher-level electrical power supply.

[0019] Furthermore, in particular, the at least one power output is configured for connecting an electrical device, for example, a field device. "Field devices" are, for example, actuators and sensors in automation technology. Other components can also be referred to as field devices, for example, measuring transducers, communication devices, control units, regulators, or measuring devices. A further device can also be connected to a power output, with which electrical power can be provided to additional devices; for example, an electrical distributor or another electrical safety device.

[0020] In particular, the electrical safety device has a plurality of power outputs. In such a case, the electrical safety device can be designed as a distribution device for electrical power. The electrical parameter of the power output monitored by the monitoring circuit can, in particular, be a current intensity.

[0021] The triggered state of the safety device can be activated, for example, by means of the control unit.

[0022] In the triggered state of the safety device, at least one power output is electrically isolated from the power input, and accordingly, devices connected to this power output are no longer supplied with electrical power via the power output. Similarly, if there are multiple power outputs, those power outputs for which the monitored electrical parameter exceeds the threshold value can be electrically isolated, whereby the threshold values ​​can be individually specified for the individual power outputs. In a further case, all power outputs of the electrical safety device can be electrically isolated from the power input.

[0023] When the electrical safety device is reset, the electrically isolated power output is electrically reconnected to the power input. In particular, all power outputs of the electrical safety device that were isolated in the triggered state are electrically connected to the power input upon reset.

[0024] This can mean that when the safety device is reset, the reset, connected state is established for all existing power outputs. Alternatively or additionally, it can be provided that one power output or several separate power outputs are reset individually, for example, by resetting them in the same order in which they were previously disconnected, or by the electrical reset parameter including information about which power output is to be reset, or by resetting the power outputs in a predetermined order, or in another way.

[0025] The invention allows, for example, the use of a digital input / output, in particular a standard input / output mode (SIO mode), of the communication interface. Via the communication pin (e.g., "pin 4" in the standard pin assignment) in SIO mode, the fuse can be acknowledged by switching an externally or internally provided voltage signal, e.g., 24 V. No external power supply is necessary, although it may be optionally provided in certain embodiments. In another embodiment, acknowledgment can be achieved by switching an entire power train off and on again. For this purpose, a so-called "smart power supply unit" (PSU) is used, which is integrated into a data network and can be controlled via such a network.

[0026] During training, the electrical safety device is designed according to the standard DIN EN 81346 (version 2019).

[0027] Alternatively or additionally, the communication interface can have a pin assignment for an IO-Link device according to the standard DIN EN 60947-5-2 (version 2021), whereby the communication pin is designed as “pin 4”, in particular for a switching and communication line, C / Q.

[0028] In a further embodiment, the electrical safety device is designed such that the communication pin is used as a switching and communication line in the reset state of the electrical safety device or in a standard input / output mode (SIO mode), in particular as an SIO input or as a communication pin (C / Q) for an IO-Link connection. In particular, in the pin assignment of an IO-Link connector, a "pin 4" can be used both for communication and as an input in SIO mode.

[0029] In a further development, the control unit is configured to reset the electrical safety device when a specific voltage of, for example, 24 V or when a voltage within a predetermined range is applied to the communication pin, for example a voltage in a range between 18 V and 30 V, preferably in a range of 20 V to 28 V, particularly preferably a voltage of 24 V.

[0030] In further embodiments, for example for applications in the automotive sector and / or mobile equipment, the control unit can be configured to reset the electrical fuse when a voltage in a specific other range is applied to the communication pin, for example in a range from 1 V to 10 V, preferably in a range from 5 V to 10 V.

[0031] This means that the electrical reset parameter in this case is a voltage, and the reset occurs depending on the voltage level. A threshold value can be specified for the electrical reset parameter; if this threshold is exceeded or undershot, the safety device is reset. Furthermore, a specific value for the reset parameter can be specified, with the safety device being reset when the specific value is reached, in particular within a specified tolerance of, for example, 10% deviation.

[0032] In further embodiments, the reset parameter can be temporally variable. For example, the control unit can be configured to reset the security device when a specific signal is present for a specific period of time, i.e., when a temporal threshold for a specific signal is exceeded. Furthermore, the reset parameter can comprise a signal pattern, such as a defined sequence of signals that are, in particular, temporally variable.

[0033] In one embodiment, the communication interface is configured such that the electrical reset parameter is obtained at the communication pin by means of an external device, in particular by applying a specific external voltage of, for example, 24 V or a voltage in a predetermined range, for example in a range between 18 V and 30 V, preferably in a range of 20 V to 28 V, particularly preferably a voltage of 24 V.

[0034] As already explained above, in further embodiments, the control unit can be configured, for example for applications in the automotive sector and / or mobile equipment, to reset the electrical fuse when a voltage in a certain other range is applied to the communication pin, for example in a range from 1 V to 10 V, preferably in a range from 5 V to 10 V.

[0035] An external device could be, for example, an external power supply. This can be connected manually by a user to reset the security device.

[0036] If the reset parameter, as explained above, is not only a fixed value of a voltage, but includes other aspects, in particular a time-varying voltage value, then this reset parameter can also be provided by an external device.

[0037] In a further embodiment, the control unit is further configured to apply a defined voltage to a signaling contact pin of the communication interface when the triggered state of the electrical safety device is activated. This can, but does not necessarily have to, be implemented with the same control unit as the reset; instead, another module, in particular another electrical assembly, can be implemented to control this circuit.

[0038] In particular, a bridge is connected from the power input to the signal contact pin.

[0039] In particular, the signaling contact pin of the communication interface can be designed as “Pin 2” of a connection assignment for an IO-Link device according to the standard DIN EN 60947-5-2 (version 2021).

[0040] This advantageously allows the existing power supply to be used without the need for an additional external power supply. By internally switching the pin assignment, one of the pins of the communication interface is used as a signaling contact. Another pin, which otherwise fulfills a role for implementing data transmission, is used to detect the bridging between the pins, and this event defines the condition for resetting the safety device.

[0041] In a further development, the signaling contact pin can be connected to the communication pin of the communication interface - particularly in the triggered state of the electrical safety device - by a plug with a bridge circuit being plugged into the communication interface and / or a user actuating a switch with a bridge circuit and / or a bridge circuit being switched using a reset signal.

[0042] This advantageously allows various methods to be used to bridge the pins of the safety device. The invention can also be easily adapted and integrated into existing safety devices.

[0043] Various aspects of the invention are summarized below in slightly modified terms.

[0044] To reset the safety device, an external voltage source can be used to apply a specific voltage, such as 24 V, to the communication pin. The communication pin can be the pin of the communication interface, designated "Pin 4" according to the standard. The safety device can then be reset. One method for resetting the safety device is to use pin 4 as an input in SIO mode, for example, and to acknowledge the safety device when a voltage of 24 V is applied.

[0045] Furthermore, when the fuse is triggered, a circuit can be activated so that a specific voltage, such as 24 V, is switched from the internal power line to a signaling contact pin, for example, the pin of the communication interface, which is standardly designated as "Pin 2." This voltage can then be applied via a bridge to the communication pin, such as "Pin 4," to acknowledge the fuse.

[0046] The safety device can be operated, for example, as an IO-Link device. This device is an IOL device.

[0047] The safety device can also be reset by switching it off and on. A so-called "smart PSU," i.e., a power supply with a communication interface, can be used for this purpose. It can remotely switch the power supply to the safety device off and on via the power supply, thus acknowledging the safety. One method for resetting the safety device involves the PSU receiving a control signal and switching it off and on again based on the control signal. The safety device can thus be acknowledged remotely.

[0048] The invention further relates to a method for operating an electrical safety device having a power input, in particular for connecting to a higher-level electrical power supply, at least one power output, in particular having a plurality of power outputs, in particular for connecting field devices or other devices, and a communication interface having at least one communication pin. In the method, in an activated, triggered state of the safety device, an electrical reset parameter is detected at the communication pin, in particular a voltage applied to the communication pin, and the electrical safety device is reset depending on the electrical reset parameter.

[0049] In particular, in the reset state, the power input is electrically connected to the at least one power output and in the triggered state, in particular, the power output is electrically separated from the power input.

[0050] The method is particularly designed to operate the device. It therefore has the same advantages as the device according to the invention and can be further developed in an analogous manner.

[0051] In one embodiment of the method, the reset parameter is a voltage applied to the communication pin.

[0052] In one implementation of the method, an external device, such as an external power supply, is connected to the communication pin to provide the reset parameter. For example, the communication pin is supplied with a specific voltage, such as 24 V.

[0053] In a further embodiment, when the triggered state of the electrical safety device is activated, a signaling contact pin of the communication interface is applied with a defined voltage. For this purpose, a bridge is connected from the power input to the signaling contact pin.

[0054] The invention is explained in more detail below with reference to the accompanying drawings. They show:

[0055] Figure 1 shows an embodiment of the safety device in a system for distributing electrical power to field devices and other devices;

[0056] Figure 2 is a schematic representation of an embodiment of the electrical safety device;

[0057] Figures 3A to 3C are schematic views of the terminals and pin assignment of the embodiment of the safety device; and

[0058] Figure 4 is a schematic representation of an embodiment of the method.

[0059] With reference to Figure 1, an embodiment of the safety device in a system for distributing electrical power to field devices and other devices is explained.

[0060] A main line 10 provides electrical power with an alternating voltage of 400 V. A higher-level electrical power supply unit (PSU) 12 is connected to the main line 10 and then provides power with a direct voltage of 24 V via a line 14.

[0061] A line in Figure 1 indicates the distinction between an alternating current range (AC range) and a direct current range (DC range).

[0062] In the exemplary embodiment, a first safety device 30 is connected to the line 14.

[0063] The electrical power is further distributed via a further line 15 from the first safety device 30 to a second safety device 31.

[0064] The safety devices 30, 31 are essentially constructed the same in the embodiment.

[0065] Devices 22 are connected to the safety devices 30, 31 and are supplied with electrical power via lines 16, 18.

[0066] The devices 22 may in particular be field devices 22, for example actuators and sensors; however, other devices may also be connected, in particular other electrical safety devices and electrical distribution devices.

[0067] Furthermore, the exemplary embodiment shows a line 20 from the second safety device 31 to one of the devices 22, wherein an IO-Link connection can be established via this line 20. For example, the device 22 can function as an IO-Link master, and the electrical safety device 31 can be operated as an IO-Link device.

[0068] An exemplary embodiment of the electrical safety device 30 is explained with reference to Figure 2. The exemplary embodiment explained above with reference to Figure 1 is assumed, and in particular, it is assumed that the electrical safety devices 30, 31 already mentioned therein are essentially identical in construction. The electrical safety device 30 has a power input 41.

[0069] In the example shown, it also has three power outputs 42, 43, 44.

[0070] It also has a communication interface 46.

[0071] Furthermore, a monitoring circuit 45 is provided, which is arranged and designed such that an electrical parameter, here namely a current intensity, is monitored for the power outputs 42, 43, 44.

[0072] The monitoring circuit 45 is configured to activate a triggered state of the safety device 30 when the detected current exceeds a threshold value. For this purpose, the power outputs 42, 43, 44 are electrically disconnected from the power input 41.

[0073] In this example, the current of each of the power outputs 42, 43, and 44 is limited to 4 A. If this current threshold is exceeded, the power outputs 42, 43, and 44 are deactivated.

[0074] The electrical safety device also has a control unit 47. When the triggered state of the safety device 30 is activated, the control unit monitors a communication pin of the communication interface 46 and checks whether an electrical reset parameter is present there.

[0075] In the embodiment, such a reset parameter is present when the communication pin is supplied with a voltage of 24 V.

[0076] If the electrical reset parameter is present, then the electrical safety device 30 is reset.

[0077] Therefore, in order to reset the safety device 30, an external voltage source can be connected to the communication interface 46, for example, in order to apply a voltage of 24 V to the communication pin.

[0078] In the exemplary embodiment, the electrical safety device 30 is designed according to the standard DIN EN 81346 (2019 version). Reference is made below to Figures 3A to 3C, which are based on the terminal assignment defined in the standard and show, by way of example, the terminals for a communication interface 32 and for power outputs 34, 36.

[0079] Furthermore, the communication interface 46 has a pinout for an IO-Link device according to the DIN EN 60947-5-2 standard (2021 version), as shown below in Figures 3A to 3C. The communication pin is configured as "Pin 4," specifically for a switching and communication line, C / Q.

[0080] When the electrical safety device 30 of the exemplary embodiment is operated in the reset state, the communication pin is used as a switching and communication line in a standard input / output (SIO) mode. The communication pin is used as an SIO input or as communication pin C / Q for an IO-Link connection.

[0081] In the exemplary embodiment, the control unit 47 applies a defined voltage to a signaling contact pin of the communication interface 46 upon activation of the triggered state. This is achieved by a bridge circuit that connects the signaling contact pin to the power input 41 in such a way that 24 V is applied. In the exemplary embodiment, "Pin 2" is used as the signaling contact pin of the communication interface 46, as provided for in the standards DIN EN 60947-5-2 (version 2021) and DIN EN 81346 (version 2019).

[0082] To reset the electrical safety device, the signaling contact pin "Pin 2" is then connected to the communication pin "Pin 4" of the communication interface 46. This then also supplies 24V to the communication pin "Pin 4". It is determined that the reset parameter is present, and the safety device 30 is reset.

[0083] To establish a bridge between pins 2 and 4, for example, a connector with a suitable circuit can be attached or plugged into the communication interface 46. Furthermore, a user can actuate a switch to switch a bridge, in particular by means of a closing contact. Furthermore, a bridge circuit can be switched using a reset signal, by means of which the connection is established.

[0084] Figure 3B shows the assignment of the IO-Link port of the exemplary embodiment of the security device 30. Furthermore, Figure 4 shows a schematic representation of an exemplary embodiment of the method, based on the device explained above.

[0085] Pins 1 and 3 of the communication interface 32 are used for an external power supply. Communication takes place via pin 4 in the reset state, while in the triggered state, an acknowledgement can be performed by applying a voltage of 24 V to pin 4.

[0086] In a first step S1, it is determined that the IO-Link port 32 is not supplied with external voltage. If necessary, it is also determined that the IO-Link port 32 is not being used by a connected device. In a step S2, when the

[0087] Fuse a voltage of 24 V is switched to pin 2 of the IO-Link port 32, so that when bridging between pin 2 and pin 4, the acknowledgement takes place in a step S3 and the safety device 30 is reset.

[0088] List of reference symbols

[0089] 10 Main line

[0090] 12 Power supply (AC); Power Supply Unit (PSU)

[0091] 14 Line (DC)

[0092] 15 Additional line (DC)

[0093] 16 Line (DC)

[0094] 18 Line (DC)

[0095] 20 cables (IO-Link)

[0096] 22 Additional device, field device

[0097] 30, 31 Electrical safety device

[0098] 32 Communication interface

[0099] 34, 36 Power output

[0100] 41 Power input

[0101] 42, 43, 44 Power output

[0102] 45 Monitoring circuit

[0103] 46 Communication interface

[0104] 47 Control unit

[0105] S1, S2, S3 step

Claims

Patent claims 1. An electrical safety device (30) having a power input (41), at least one power output (42, 43, 44), and a monitoring circuit (45) for monitoring an electrical parameter of the power output (42, 43, 44); wherein the monitoring circuit (45) is configured to activate a triggered state of the safety device (30) as a function of the electrical parameter, in particular when the electrical parameter exceeds a threshold value, in which the power output (42, 43, 44) is electrically separated from the power input (41); further provided is: a communication interface (46) having at least one communication pin (pin 4); and a control unit (47) configured to reset the electrical safety device (30) in the triggered state of the safety device (30) as a function of an electrical reset parameter on the communication pin of the communication interface (46).

2. Electrical safety device (30) according to claim 1, characterized in that the electrical safety device (30) is designed according to the standard DIN EN 81346 (version 2019); and / or the communication interface (46) has a pin assignment for an IO-Link device according to the standard DIN EN 60947-5-2 (version 2021), wherein the communication pin is designed as "pin 4", in particular for a switching and communication line, C / Q.

3. Electrical safety device (30) according to one of the preceding claims, characterized in that the electrical safety device (30) is designed such that the communication pin is used as a switching and communication line in the reset state of the electrical safety device (30) or in a standard input-output mode, SIO mode, in particular as SIO input or as communication pin, C / Q, for an IO-Link connection.

4. Electrical safety device (30) according to one of the preceding claims, characterized in that the control unit (47) is configured to reset the electrical safety device (30) as a function of a voltage at the communication pin, in particular when a specific voltage of, for example, 24 V is applied to the communication pin or when a voltage within a predetermined range is applied, for example a voltage in a range between 18 V and 30 V, preferably in a range of 20 V to 28 V, particularly preferably a voltage of 24 V.

5. Electrical safety device (30) according to one of the preceding claims, characterized in that the communication interface (46) is set up such that the electrical reset parameter is obtained at the communication pin by means of an external device, in particular by applying a specific external voltage of, for example, 24 V or a voltage in a predetermined range, for example in a range between 18 V and 30 V, preferably in a range of 20 V to 28 V, particularly preferably a voltage of 24 V.

6. Electrical safety device (30) according to one of the preceding claims, characterized in that the control unit (47) is further configured, when the triggered state of the electrical safety device (30) is activated, to apply a defined voltage to a signaling contact pin (pin 2) of the communication interface (46); wherein, in particular, a bridge is connected from the power input (41) to the signaling contact pin (pin 2) for this purpose; wherein, in particular, the signaling contact pin of the communication interface (46) is designed as "pin 2" of a connection assignment for an IO-Link device according to the standard DIN EN 60947-5-2 (version 2021).

7. Electrical safety device (30) according to the preceding claim, characterized in that the signaling contact pin (pin 2) can be connected to the communication pin (pin 4) of the communication interface by attaching or plugging in a plug with a bridge to the communication interface (46) and / or a user actuating a switch with a bridge and / or switching a bridge based on a reset signal.

8. A method for operating an electrical safety device (30) having a power input (41), at least one power output (42, 43, 44), and a communication interface (46) having at least one communication pin (pin 4); wherein, in an activated, triggered state of the electrical safety device (30), an electrical reset parameter is detected at the communication pin (pin 4); and the electrical safety device (30) is reset as a function of the electrical reset parameter.

9. Method according to the preceding method claim, characterized in that the reset parameter is a voltage applied to the communication pin (pin 4).

10. Method according to the preceding method claim, characterized in that an external device is connected to the communication pin (pin 4) to provide the reset parameter.

11. Method according to one of the preceding method claims, characterized in that, when the triggered state of the electrical safety device (30) is activated, a signaling contact pin (pin 2) of the communication interface (46) is subjected to a defined voltage; in particular, for this purpose, a bridge is connected from the power input (41) to the signaling contact pin (pin 2).

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