Circuit breaker

Description

[0001] The present invention relates to a device for protecting an electrical installation and a method of operating such a protection device.

[0002] An electrical installation in a building generally includes an electrical panel, connecting this electrical installation to a collective electricity distribution network and including various devices for protecting, controlling and monitoring the electrical installation. Among the electrical protection devices, we know in particular a circuit breaker, which aims to protect the electrical installation or a person against an electrical fault in an electrical circuit of the installation, by opening the electrical circuit. For example, the circuit breaker is triggered by an overload, a short circuit or a differential electrical fault within this circuit.

[0003] Such circuit breakers typically include an arc chute configured to extinguish an electric arc that appears in the air between the circuit breaker's electrical contacts when the electrical contacts are separated following a circuit breaker trip. The arc chute typically includes a stack of metal plates stacked on top of each other to extend and extinguish the electric arc. One or more holes in the circuit breaker housing allow the cutting gases to be vented outside the circuit breaker.

[0004] However, in order to improve the performance of these protection devices, it has been proposed to replace the breaking chamber with an electronic breaking device comprising power switches based on semiconductor components. Such protection devices have a high breaking capacity and allow particularly rapid breaking, thus considerably reducing the breaking arc. Such a protection device provided with an electronic breaking device comprising power switches based on semiconductor components is for example known from document FR 3 123 141 A1. GB2182812A describes a device for supplying current to a circuit with one or more phases, comprising means for interrupting the current in the event of a fault such as a short circuit.

[0005] However, such devices have higher production costs than the production costs of conventional protective devices.

[0006] The aim of the invention is therefore to propose an inexpensive protection device allowing particularly rapid cut-off and having a high cut-off capacity.

[0007] To this end, the invention relates to a device for protecting an electrical installation according to claim 1. The invention also relates to a method of operating a protection device according to claim 6.

[0008] According to other advantageous aspects of the invention, the protection device comprises one or more of the characteristics of claims 2 to 5, taken individually or in all technically possible combinations.

[0009] According to further advantageous aspects of the invention, the operating method comprises one or more of the features of claims 7 to 12, taken individually or in all technically possible combinations.

[0010] The invention will appear more clearly on reading the description which follows, given solely by way of non-limiting example, and made with reference to the drawings in which: [ Fig. 1 ] there figure 1 is a schematic representation of a protection device according to one embodiment; [ Fig. 2 ] there figure 2 is a schematic representation of the protection device according to the embodiment illustrating a short circuit; [ Fig. 3 ] there figure 3 is a graphical representation of an example of a sequence of steps of a method of operating the protection device according to the embodiment in the case of a short circuit; [ Fig. 4 ] there figure 4 is a schematic representation of the protection device according to the embodiment illustrating an overload; [ Fig. 5 ] there figure 5 is a graphical representation of an example of a sequence of steps of the operating method of the protection device according to the embodiment in the case of an overload; [ Fig. 6 ] there figure 6 is a schematic representation of the protection device according to the embodiment illustrating a differential fault; and [ Fig. 7 ] there figure 7 is a graphical representation of an example of a sequence of steps in the operating method of the protection device according to the embodiment in the case of a differential fault.

[0011] The present application relates to a protection device 10 for an electrical installation as well as a method of operating such a protection device 10. The figure 1 is a schematic representation of the preferred embodiment of the protection device 10.

[0012] The protection device 10 comprises a pair of input terminals 12, 14, an input line 16 provided with two input conductors 16L, 16N each connected to one of the input terminals 12, 14, a plurality of output lines 18, 20, 22 connected in parallel to the input line 16, each output line 18, 20, 22 being provided with two output conductors 18L, 18N, 20L, 20N, 22L, 22N, an output current measuring device 24, 26, 28 and being capable of supplying a downstream electrical installation, an electronic cut-off device 40 comprising power switches 42, 44 based on semiconductor components connected in series between the input line 16 and the output line 18, 20, 22, a control unit 50 capable of controlling the electronic cut-off device 40.

[0013] The control unit 50 is further capable of receiving a signal representative of an output current of each output line 18, 20, 22 measured by the output current measuring device 24, 26, 28 of this output line 18, 20, 22. One of the output conductors 18L, 18N, 20L, 20N, 22L, 22N of each output line 18, 20, 22 is provided with a switch 30, 32, 34 controllable by the control unit 50 to switch the switch 30, 32, 34 between an open position and a closed position and vice versa.

[0014] The protection device 10 according to the present application comprises at least two output lines 18, 20, 22 each capable of supplying a downstream electrical installation. The protection device 10 according to the present embodiment comprises three output lines 18, 20, 22 each capable of supplying a downstream electrical installation: a first output line 18 capable of supplying a first downstream electrical installation, a second output line 20 capable of supplying a second downstream electrical installation and a third output line 22 capable of supplying a third downstream electrical installation.

[0015] The protection device 10 may further be provided with output terminals each connected to one of the output conductors 18L, 18N, 20L, 20N, 22L, 22N.

[0016] The switch 30, 32, 34 of each output line 18, 20, 22 is connected to the output conductor 18L, 18N, 20L, 20N, 22L, 22N constituting the phase conductor 18L, 20L, 22L of the output line 18, 20, 22 and makes it possible to interrupt the current in the phase conductor 18L, 20L, 22L. The switch 30, 32, 34 of each output line 18, 20, 22 may consist of a relay that can be controlled by the control unit 50 to switch the relay between an open position and a closed position and vice versa. Alternatively, the switch 30, 32, 34 of each output line 18, 20, 22 may consist of a disconnector controllable by the control unit 50 to switch the disconnector between an open position and a closed position and vice versa.

[0017] According to one possibility, the input conductors 16L, 16N may comprise separable electrical contacts 36 arranged between the pair of input terminals 12, 14 and the electronic cut-off device 40, the protection device 10 further comprising an actuator 33 controllable by the control unit 50 and capable of switching the separable electrical contacts 36 between a closed position and an open position and vice versa.

[0018] The protection device 10 may comprise a handle. The handle may be adapted to send a command to open the separable electrical contacts 36 to the control unit 50 following an action by a user on the handle. Following receipt of the command to open the separable electrical contacts 36 by the control unit 50, the control unit 50 may open the electronic cut-off device 40 to cut off the current in the downstream electrical installations. Then, the control unit 50 may further open the separable electrical contacts 36 for sectioning.

[0019] The input line 16 may be provided with an input current measuring device 38, the control unit 50 being further capable of receiving a signal representative of an input current measured by the input current measuring device 38.

[0020] Additionally or alternatively, the input line 16 may be provided with a differential current measuring device 39, the control unit 50 being further capable of receiving a signal representative of a differential current measured by the differential current measuring device 39.

[0021] The input line 16 is provided with a voltage measuring device, the control unit 50 being further capable of receiving a signal representative of a voltage measured by the voltage measuring device.

[0022] As represented in the figure 1 , the protection device 10 may further comprise a power supply module 35 capable of supplying the control unit 50 with electrical energy. The power supply module 35 may be, on the one hand, connected to the control unit 50 and, on the other hand, connected to the input line, preferably between the separable electrical contacts 36 and the electronic cut-off device 40. Thus, opening the separable contacts 36 allows galvanic isolation of the electronic cut-off device 40.

[0023] Alternatively, the power supply module 35 can be connected to the input line upstream of the separable electrical contacts 36, for example between the separable electrical contacts 36 and the input terminals 12, 14. Thus, a power supply to the control unit 50 can be ensured even in the open position of the separable electrical contacts 36. This is particularly advantageous when the protection device 10 comprises a display module, for example provided with a plurality of light-emitting diodes and / or a liquid crystal screen displaying information to a user such as the nature of the fault that caused the outage.

[0024] The voltage measuring device may be an integral part of the power supply module 35.

[0025] The protection device 10 may further comprise a control circuit 46 capable of controlling the opening and / or closing of the power switches 42, 44 based on semiconductor components of the electronic cut-off device 40 following receipt of an opening or closing command from the control unit 50.

[0026] The protection device 10 may further comprise an analog-to-digital converter 31 connected, on the one hand, to the output current measuring devices 24, 26, 28, to the input current measuring device 38 and / or to the differential current measuring device 39 and, on the other hand, to the control unit 50. The analog-to-digital converter 31 is capable of converting an analog signal originating from the output current measuring devices 24, 26, 28 into a digital signal representative of an output current measured by the output current measuring devices 24, 26, 28. The analog-to-digital converter 31 is further capable of converting an analog signal originating from the input current measuring device 38 into a digital signal representative of an input current measured by the input current measuring device 38.The analog-to-digital converter 31 is also capable of converting an analog signal from the differential current measuring device 39 into a digital signal representative of a differential current measured by the differential current measuring device 39.

[0027] The control unit 50 comprises a computing unit and a memory and can further be provided with a communication interface 52.

[0028] The control unit 50 is capable of determining whether the signals representative of the output current of each output line 18, 20, 22 correspond to a short circuit occurring in one of the downstream electrical installations supplied by one of the output lines 18, 20, 22 and / or to an overload occurring in one of the downstream electrical installations supplied by one of the output lines 18, 20, 22.

[0029] The control unit 50 may also be able to determine whether the signal representing the differential current corresponds to a differential output occurring in one of the downstream electrical installations supplied by one of the output lines 18, 20, 22.

[0030] According to one possibility, the control unit 50 is able to determine whether the signal representative of the voltage corresponds to a voltage lower or higher than a minimum voltage for proper operation of the electronic cut-off device 40 and whether the signal representative of the voltage corresponds to a voltage higher or lower than a maximum voltage for proper operation of the electronic cut-off device 40 and possibly to a maximum voltage for proper operation of one of the downstream electrical installations.

[0031] The method of operation of the protection device 10 comprises the following successive steps: a. reception by the control unit 50, for each output line 18, 20, 22, of a signal representative of an output current coming from the output current measuring device 24, 26, 28 of the output line 18, 20, 22; b. determination 120 by the control unit 50 whether the signals representative of the output current of each output line 18, 20, 22 correspond to a short circuit occurring in one of the downstream electrical installations supplied by one of the output lines 18, 20, 22; c. when a short circuit has been determined in one of the downstream electrical installations: i. opening 140 of the electronic cut-off device 40; ii. opening 150 of the switch 30, 32, 34 of the output line 18, 20, 22 in which the short circuit has been determined; and iii. closing 160 of the electronic cut-off device 40.

[0032] When a short circuit 100 occurs for example in the third downstream electrical installation or the third output line 22, as illustrated by the figure 2 and the figure 3 , the output current measuring device 28 of the third output line 22 measures 110 a short-circuit current in the third output line 22.

[0033] The control unit 50 then receives the signals representative of the output current of each output line 18, 20, 22, in particular the signal representative of the output current of the third output line 22, preferably from the analog-digital converter 31. The control unit 50 subsequently determines 120 that the signal representative of the output current of the third output line 22 corresponds to a short-circuit current and transmits 130 an opening command to the control circuit 46 of the electronic cut-off device 40 to open 140 the electronic cut-off device 40. Following the opening of the electronic cut-off device 40, the control unit 50 commands the opening 150 of the switch 34 of the third output line 22.Preferably, the control unit 50 commands the opening 150 of the switch 34 of the third output line 22 when the signal representative of the output current of the third output line 18, 20, 22 corresponds to a zero crossing of the output current of the third output line 22. Following the opening of the switch 34 of the third output line 22, the control unit 50 commands the closing 160 of the electronic cut-off device 40.

[0034] Preferably, the steps of opening 140 of the electronic cut-off device 40, of opening 150 of the switch 30, 32, 34 and of closing 160 of the electronic cut-off device 40 are executed in a time space of less than 10 milliseconds.

[0035] The operating method may further comprise the following successive steps: a. determination 220 by the control unit 50 whether the signals representative of the output current of each output line 18, 20, 22 correspond to an overload occurring in one of the downstream electrical installations supplied by one of the output lines 18, 20, 22; b. when an overload has been determined in one of the downstream electrical installations: i. opening 230 of the switch 30, 32, 34 of the output line 18, 20, 22 in which the overload has been determined.

[0036] When an overload 200 occurs for example in the third downstream electrical installation or the third output line 22, as illustrated by the figure 4 and the figure 5 , the output current measuring device 28 of the third output line 22 measures 110 an overload current in the third output line 22.

[0037] The control unit 50 then receives the signals representative of the output current of each output line 18, 20, 22, in particular the signal representative of the output current of the third output line 22, preferably from the analog-digital converter 31. The control unit 50 subsequently determines 220 that the signal representative of the output current of the third output line 22 corresponds to an overload current and opens 230 the switch 34 of the third output line 22. Preferably, the control unit 50 commands the opening 230 of the switch 34 of the third output line 22 when the signal representative of the output current of the third output line 18, 20, 22 corresponds to a zero crossing of the output current of the third output line 22.

[0038] In the event of a short circuit or overload occurring in one of the downstream electrical installations, the downstream electrical installation in which the short circuit or overload occurred is protected, the other electrical installations not affected by the short circuit or overload remaining powered with an interruption time of less than 10 milliseconds.

[0039] According to one possibility, a current threshold can be defined for each output line 18, 20, 22, an overload in one of the output lines 18, 20, 22 being determined when the signal representative of the output current of this output line 18, 20, 22 corresponds to a current whose intensity exceeds the current threshold defined for this output line 18, 20, 22. The current threshold defined for each output line 18, 20, 22 can for example be stored in the memory of the control unit 50.

[0040] The current threshold defined for each output line 18, 20, 22 can for example be defined by a user through a user interface in communication link with the communication interface 52 of the control unit 50. The current threshold defined for each output line 18, 20, 22 can be transmitted from the user interface to the communication interface 52 of the control unit 50 via the communication link and then stored in the memory of the control unit 50.

[0041] Alternatively, the current threshold defined for each output line 18, 20, 22 can be defined by software running on a remote server in communication link with the communication interface 52 of the control unit 50 for example. The current threshold defined for each output line 18, 20, 22 can be transmitted from the remote server to the communication interface 52 of the control unit 50 via the communication link and then stored in the memory of the control unit 50.

[0042] Alternatively, a load protection curve adapted to the downstream electrical installation connected to the output line 18, 20, 22 can be defined for each output line 18, 20, 22 respectively, an overload in one of the output lines 18, 20, 22 being determined when the signal representative of the output current of this output line 18, 20, 22 corresponds to a fault situation according to the protection curve defined for the downstream electrical installation connected to this output line 18, 20, 22. The protection curve adapted to the downstream electrical installation can for example be stored in the memory of the control unit 50.

[0043] The protection curve adapted to the downstream electrical installation connected to the output line 18, 20, 22 can for example be defined by a user through a user interface in communication link with the communication interface 52 of the control unit 50. The adapted protection curve can be transmitted from the user interface to the communication interface 52 of the control unit 50 via the communication link and then stored in the memory of the control unit 50.

[0044] The operating method may further comprise the following successive steps: a. reception by the control unit 50 of a signal representative of a differential current coming from the differential current measuring device 39; b. determination 320 by the control unit 50 whether the signal representative of the differential current corresponds to a differential output occurring in one of the downstream electrical installations supplied by one of the output lines 18, 20, 22; c. when a differential output has been determined in one of the downstream electrical installations: i. opening 330 of the electronic cut-off device 40; and ii. opening 340 of the separable electrical contacts 36.

[0045] The differential departure can, for example, be the result of the appearance of a leakage current in one of the downstream electrical installations or the result of the appearance of an arc fault to earth in one of the downstream electrical installations.

[0046] When a differential departure 300 intervenes for example in the third downstream electrical installation or the third output line 22, as illustrated by the figure 6 and the figure 7 , the differential current measuring device 39 measures 310 a differential current corresponding to a differential departure in one of the output lines 18, 20, 22.

[0047] The control unit 50 then receives a signal representative of a differential current preferably from the analog-digital converter 31. The control unit 50 subsequently determines 320 that the signal representative of the differential current corresponds to a differential feeder occurring in one of the downstream electrical installations supplied by one of the output lines 18, 20, 22 and commands the opening 330 of the electronic cut-off device 40. Then, the control unit 50 commands the opening 340 of the separable electrical contacts 36.

[0048] The operating method further comprises the following successive steps: a. reception by the control unit 50 of a signal representative of a voltage coming from the voltage measuring device; b. determination by the control unit 50 whether the signal representative of the voltage corresponds to a voltage lower than a minimum voltage for proper operation of the electronic cut-off device 40; c. when a voltage lower than the minimum voltage for proper operation of the electronic cut-off device 40 has been determined: i. opening of the electronic cut-off device 40. The operating method may then comprise the following successive steps: ii. opening of the switch 30, 32, 34 of each output line 18, 20, 22; d. determination by the control unit 50 whether the signal representative of the voltage corresponds to a voltage higher than the minimum voltage for proper operation of the electronic cut-off device 40; e.when a voltage higher than the minimum voltage for proper operation of the electronic cut-off device 40 has been determined: i. closing of the electronic cut-off device 40; and ii. closing of the switch 30, 32, 34 of each output line 18, 20, 22.

[0049] If the measured voltage exceeds the minimum voltage for proper operation, for example a voltage of 100 V, the electronic cut-off device 40 is powered and protection of the downstream electrical installations is ensured.

[0050] If the measured voltage is below the minimum operating voltage, the electronic cut-off device 40 is opened to cut off the current in the downstream electrical installations and each switch 30, 32, 34 is opened for galvanic isolation of the downstream electrical installations. Since the measured voltage is too low, the loads should also not be powered (undervoltage protection).

[0051] Thus, since the proper functioning of the electronic cut-off device 40 depends on the presence of a minimum operating voltage, when the voltage is at zero, for example in the event of a break in the neutral conductor, protection cannot be ensured by the electronic cut-off device 40, even if a voltage persists on the phase conductor.

[0052] When the measured voltage returns to a normal level, the electronic cut-off device 40 can be closed again, as well as the switches 30, 32, 34 to re-supply the downstream electrical installations. And the protection of the downstream electrical installations is thus once again ensured.

[0053] This mode of operation is recognized by classification 4.1.5 in the IEC61008 / 9 standard.

[0054] The operating method further comprises the following successive steps: a. reception by the control unit 50 of a signal representative of a voltage coming from the voltage measuring device; b. determination by the control unit 50 whether the signal representative of the voltage corresponds to a voltage higher than a maximum voltage for proper operation of the electronic cut-off device 40; c. when a voltage higher than the maximum voltage for proper operation of the electronic cut-off device 40 has been determined: i. opening of the electronic cut-off device 40; and ii. opening of the switch 30, 32, 34 of each output line 18, 20, 22. The operating method may then comprise the following successive steps: d. determination by the control unit 50 whether the signal representative of the voltage corresponds to a voltage lower than the maximum voltage for proper operation of the electronic cut-off device 40; e.when a voltage lower than the maximum voltage for proper operation of the electronic cut-off device 40 has been determined: i. closing of the electronic cut-off device 40; and ii. closing of the switch 30, 32, 34 of each output line 18, 20, 22.

[0055] Since the electronic cut-off device 40 with semiconductor components is generally very sensitive to overvoltages, these additional process steps ensure the reliability of the protection device 10.

[0056] When the measured overvoltage is of a temporary nature, the opening of the electronic cut-off device 40 and the switches 30, 32, 34 is carried out until the overvoltage disappears for the galvanic isolation of the downstream electrical installations and of the electronic cut-off device 40 and for the protection of the electronic cut-off device 40 and of the downstream electrical installations.

[0057] When the measured overvoltage persists, for example for a period greater than 10 minutes, the method may include opening the separable electrical contacts 36 for sectioning.

[0058] The method may further comprise a step of calculating an electrical consumption of at least one of the electrical installations as a function of the measured voltage and the measured output current for the output line 18, 20, 22 connected to this electrical installation by the control unit 50. This step allows a user and / or the control unit of the protection device 10 to monitor the electrical consumption of this electrical installation.

[0059] The method may further comprise a step of switching off one of the downstream electrical installations following receipt of a remote opening command for the switch 30, 32, 34 of the output line 18, 20, 22 connected to this electrical installation by the control unit 50. The remote opening command for the switch 30, 32, 34 of the output line 18, 20, 22 may for example be sent to the control unit 50 via its communication interface 52. The remote opening command for the switch 30, 32, 34 of the output line 18, 20, 22 may be previously entered by a user in a user interface which is in communication link with the communication interface 52 of the control unit 50.

[0060] The step of switching off one of the downstream electrical installations can be carried out by opening the switch 30, 32, 34 of the output line 18, 20, 22 connected to this downstream electrical installation when the current passing through this output line 18, 20, 22 passes through zero. Alternatively, the step of switching off one of the downstream electrical installations can be carried out by first opening the electronic cut-off device 40 and then the switch 30, 32, 34 of the output line 18, 20, 22 connected to this downstream electrical installation.

[0061] The method may further comprise a step of energizing one of the downstream electrical installations following receipt of a command to close the switch 30, 32, 34 of the output line 18, 20, 22 connected to this electrical installation by the control unit 50.

[0062] The command to close the switch 30, 32, 34 of the output line 18, 20, 22 can for example be sent to the control unit 50 via its communication interface 52. The command to close the switch 30, 32, 34 of the output line 18, 20, 22 can be previously entered by a user in a user interface which is in communication link with the communication interface 52 of the control unit 50.

[0063] The step of energizing one of the downstream electrical installations can be carried out by closing the switch 30, 32, 34 of the output line 18, 20, 22 connected to this downstream electrical installation when the voltage present on this output line 18, 20, 22 passes through zero. Alternatively, the step of energizing one of the downstream electrical installations can be carried out by first opening the electronic cut-off device 40, then closing the switch 30, 32, 34 of the output line 18, 20, 22 connected to this downstream electrical installation and subsequently closing the electronic cut-off device 40.

[0064] The operating method may further comprise the following successive steps: a. definition of a load shedding current threshold; b. assignment of a priority degree to each output line 18, 20, 22; c. when the sum of the currents of each output line 18, 20, 22 corresponding to the signal representative of the output current of this line exceeds the load shedding current threshold or when the input current corresponding to the signal representative of the input current exceeds the load shedding current threshold: i. opening of the switch 30, 32, 34 of the output line 18, 20, 22 to which the lowest priority degree has been assigned among the priority degrees of each output line 18, 20, 22.

[0065] The load shedding current threshold can for example be sent to the control unit 50 via its communication interface 52. The load shedding current threshold can be previously entered by a user in a user interface which is in communication link with the communication interface 52 of the control unit 50. Alternatively, the load shedding current threshold can for example be imposed by an agreement with an electricity supplier during certain predefined time slots. Alternatively, the load shedding current threshold can correspond to a rating of the protection device 10.

[0066] Thanks to the electronic cut-off device 40, the protection device 10 and the operating method of the protection device 10 allow rapid interruption of the current in the event of a short circuit minimizing the cut-off arc, the switch 30, 32, 34 of the output line 18, 20, 22 corresponding to the downstream electrical installation in which the short circuit occurred being open during the brief period during which the electronic cut-off device 40 is open. In the event of the occurrence of a short circuit, it is possible to waive the waiting for the current to cross to zero before opening the switch 30, 32, 34 of the output line 18, 20, 22 corresponding to the downstream electrical installation in which the short circuit occurred.

[0067] The protection device 10 and the method of operating the protection device 10 according to the present application allow several downstream electrical installations to benefit from the performance of the electronic cut-off device 40 without requiring an electronic cut-off device for each output line. The protection device 10 and the method of operating the protection device 10 according to the present application also allow them to be configured by an update of software executed by the control unit 50.

[0068] The protection device 10 and the method of operating the protection device 10 according to the present application have the further advantage of making it possible to add new functions, such as new protection, service continuity, remote configuration, preventive maintenance and / or load management functions, for a plurality of downstream electrical installations.

Claims

1. A device for protecting an electrical installation, comprising a pair of input terminals (12, 14), an input line (16) provided with two input conductors (16L, 16N) each connected to one of the input terminals (12, 14), at least one output line (18, 20, 22) connected to the input line (16), provided with two output conductors (18L, 18N, 20L, 20N, 22L, 22N) and able to supply a downstream electrical installation, an electronic breaking device (40) comprising power switches (42, 44) based on semiconductor components connected in series between the input line (16) and the output line (18, 20, 22), and a control unit (50) able to control the electronic breaking device (40), the protection device comprises a plurality of output lines (18, 20, 22) connected in parallel to the input line (16), each output line (18, 20, 22) being provided with two output conductors (18L, 18N, 20L, 20N, 22L, 22N), an output current measuring device (24, 26, 28) and being able to supply a downstream electrical installation, the control unit (50) also being able to receive a signal representative of an output current of each output line (18, 20, 22) measured by the output current measuring device (24, 26, 28) of this output line (18, 20, 22), and one of the output conductors (18L, 18N, 20L, 20N, 22L, 22N) of each output line (18, 20, 22) is provided with a switch (30, 32, 34) controllable by the control unit (50) to switch the switch (30, 32, 34) between an open position and a closed position and vice versa, characterised in that the input line (16) is provided with a voltage measuring device, the control unit (50) also being able to receive a signal representative of a voltage measured by the voltage measuring device, the control unit (50) is configured to determine whether the signal representative of the voltage corresponds to a voltage lower than a minimum correct operating voltage of the electronic switching device (40), or to a voltage higher than a maximum correct operating voltage of the electronic switching device (40), and the electronic breaking device (40) and the switch (30, 32, 34) of each output line (18, 20, 22) are configured to open when a voltage lower than the minimum operating voltage of the electronic breaking device (40) has been determined or when a voltage higher than the maximum operating voltage of the electronic breaking device (40) has been determined.

2. The protection device according to claim 1, characterised in that the switch (30, 32, 34) of each output line (18, 20, 22) consists of a relay which can be controlled by the control unit (50) to switch the relay between an open position and a closed position and vice versa.

3. The protection device according to any one of claims 1 or 2, characterised in that each input conductor (16L, 16N) comprises separable electrical contacts (36) arranged between the pair of input terminals (12, 14) and the electronic breaking device (40), the protection device further comprising an actuator controllable by the control unit (50) and capable of switching the separable electrical contacts (36) between a closed position and an open position and vice versa.

4. The protection device according to any one of claims 1 to 3, characterised in that the input line (16) is provided with an input current measuring device (38) and / or a differential current measuring device (39), the control unit (50) being further adapted to receive a signal representative of an input current measured by the input current measuring device (38) and / or adapted to receive a signal representative of a differential current measured by the differential current measuring device (39).

5. The protection device according to any one of claims 1 to 4, characterised in that the control unit (50) is configured to: - receive, for each output line (18, 20, 22), a signal representative of an output current from the output current measuring device (24, 26, 28) of the output line (18, 20, 22), - determine (120) whether the signals representative of the output current of each output line (18, 20, 22) correspond to a short-circuit occurring in one of the downstream electrical installations supplied by one of the output lines (18, 20, 22), and, - when a short-circuit has been identified in one of the downstream electrical installations: ∘ transmit (130) an opening command to the control circuit (46) of the electronic switching device (40) to open (140) the electronic switching device (40), ∘ command the opening (150) of the switch (30, 32, 34) of the output line (18, 20, 22) in which the short-circuit has been determined, and ∘ - command the closing (160) of the electronic breaking device (40).

6. A method for operating a protection device according to any one of claims 1 to 5, comprising the following successive steps: a. receiving, by the control unit (50), for each output line (18, 20, 22), of a signal representative of an output current from the output current measuring device (24, 26, 28) of the output line (18, 20, 22); b. determining (120) by the control unit (50) whether the signals representing the output current of each output line (18, 20, 22) correspond to a short-circuit occurring in one of the downstream electrical installations supplied by one of the output lines (18, 20, 22); c. when a short-circuit has been identified in one of the downstream electrical installations: i. opening (140) the electronic breaking device (40); ii. opening (150) the switch (30, 32, 34) of the output line (18, 20, 22) in which the short-circuit has been determined; and iii. closing (160) the electronic breaking device (40), characterised in that it further comprises the following steps: a. the control unit (50) receives a signal representative of a voltage from the voltage measuring device; b. determining, by the control unit (50), whether the signal representative of the voltage corresponds to a voltage below a minimum correct operating voltage of the electronic switching device (40) or to a voltage above a maximum correct operating voltage of the electronic switching device (40); c. when a voltage lower than the minimum operating voltage of the electronic switching device (40), or a voltage higher than the maximum operating voltage of the electronic switching device (40) has been determined: i. opening the electronic breaking device (40); and ii. opening the switch (30, 32, 34) on each output line (18, 20, 22).

7. The method for operation according to claim 6, characterised by the following successive steps: a. determining (220) by the control unit (50) whether the signals representing the output current of each output line (18, 20, 22) correspond to an overload occurring in one of the downstream electrical installations supplied by one of the output lines (18, 20, 22); b. when an overload has been determined in one of the downstream electrical installations: i. opening (230) the switch (30, 32, 34) of the output line (18, 20, 22) in which the overload has been determined.

8. The method for operation according to claim 7, characterised in that a current threshold is defined for each output line (18, 20, 22), an overload in one of the output lines (18, 20, 22) being determined when the signal representative of the output current of that output line (18, 20, 22) corresponds to a current whose intensity exceeds the current threshold defined for that output line (18, 20, 22).

9. The method for operation according to any one of claims 6 to 8, the protection device being a protection device according to a combination of claims 3 and 4, the method being characterised by the following successive steps: a. reception by the control unit (50) of a signal representative of a differential current from the differential current measuring device (39); b. determination (320) by the control unit (50) whether the signal representing the differential current corresponds to a differential fault occurring in one of the downstream electrical installations supplied by one of the output lines (18, 20, 22); c. when a differential fault has been determined in one of the downstream electrical installations: i. opening (330) the electronic breaking device (40); and ii. opening (340) the separable electrical contacts (36).

10. The method of operation according to any one of claims 6 to 9, the protection device being a protection device according to any one of claims 1 to 5, the method being characterised by the following successive steps: d. after opening the electronic breaking device (40) and opening the switch (30, 32, 34) of each output line (18, 20, 22) following determination by the control unit (50) that the representative signal corresponds to a voltage lower than the minimum correct operating voltage of the electronic breaking device, determining, by the control unit (50), if the signal representative of the voltage corresponds to a voltage higher than the minimum correct operating voltage of the electronic breaking device (40); e. when a voltage higher than the minimum operating voltage of the electronic switching device (40) has been determined: i. closing the electronic breaking device (40); and ii. closing the switch (30, 32, 34) on each output line (18, 20, 22).

11. The method for operation according to any one of claims 6 to 10, the protection device being a protection device according to any one of claims 1 to 5, the method being characterised by the following successive steps: d. after opening the electronic breaking device (40) and opening of the switch (30, 32, 34) of each output line (18, 20, 22) following determination by the control unit (50) that the representative signal corresponds to a voltage higher than the maximum correct operating voltage of the electronic breaking device, determining by the control unit (50) if the signal representative of the voltage corresponds to a voltage lower than the maximum correct operating voltage of the electronic breaking device (40); e. when a voltage lower than the maximum operating voltage of the electronic switching device (40) has been determined: i. closing the electronic breaking device (40); and ii. closing the switch (30, 32, 34) on each output line (18, 20, 22).

12. A method for operation according to any one of claims 6 to 11, characterised by the following successive steps: a. defining a load-shedding current threshold; b. assigning a priority level to each output line (18, 20, 22); c. when the sum of the currents of each output line (18, 20, 22) corresponding to the signal representative of the output current of this line exceeds the load-shedding current threshold or when the input current corresponding to the signal representative of the input current exceeds the load-shedding current threshold: i. opening the switch (30, 32, 34) of the output line (18, 20, 22) which has been assigned the lowest priority level among the priority levels of each output line (18, 20, 22).