CN112670947A

CN112670947A - Protection device for AC electrical equipment

Info

Publication number: CN112670947A
Application number: CN202011111420.9A
Authority: CN
Inventors: D·马赛; G·布特卢
Original assignee: Legrand SNC; Legrand France SA
Current assignee: Legrand SNC; Legrand France SA
Priority date: 2019-10-16
Filing date: 2020-10-16
Publication date: 2021-04-16
Also published as: EP3809440B1; PL3809440T3; RU2020133593A; FR3102292A1; FR3102292B1; AU2020256418A1; EP3809440A1; ES2908414T3

Abstract

The invention relates to a protection device for an alternating current electrical apparatus, equipped with a compact element comprising a magnetic breaking coil and a protective relay coil, and an electronic circuit connected to the protective relay coil, characterized in that the electronic circuit comprises a long-time overcurrent detector (60) and comprises a switching circuit (61) configured to connect the protective relay coil to the long-time overcurrent detector (60) and to isolate the protective relay coil from input connection terminals of the device in the absence of a detection signal, and to isolate the protective relay coil from the long-time overcurrent detector (60) and then to connect the protective relay coil to the input connection terminals (22,23) in the presence of a detection signal by the switching circuit (61).

Description

Protection device for AC electrical equipment

Technical Field

The present invention relates to a protection device for an ac electrical apparatus.

Background

From the prior art, and in particular from french patent application 3046289, it is known to provide protection devices for alternating current electrical apparatuses, as shown in figures 1 to 3 of the accompanying drawings, in which:

fig. 1 is a perspective view of such a known protective device, taken from the top, front and right side of the device;

figure 2 shows, in a very schematic way, the electric circuit of a first embodiment of the known device and the control mechanism of the movable contacts that it comprises; and is

Fig. 3 shows, in a very schematic way, the electric circuit of a second embodiment of the known device and the control mechanism of the movable contacts that it comprises.

The electrical device 10 shown in fig. 1 has a substantially parallelepiped shape.

It has two main surfaces, a left surface 11 and a right surface 12, respectively, and side surfaces extending from one of the main surfaces 11 and 12 to the other, i.e., a back surface 13, an upper surface 14, a front surface 15 and a lower surface 16.

The back face 13 has a notch 17 for mounting the device 10 on a standard support rail (not shown) having an omega profile.

The front surface 15 has a nose 18 with a lever 19 in a central position, about half its length.

The device 10 is of the modular type, that is to say, apart from its overall parallelepiped shape, its width (distance between the two main surfaces 11 and 12) is a multiple of a standardized value called "module", which is about 18 mm.

Here, the device 10 has a width of the modulus.

The device 10, according to the modular form, is configured to belong to a row of modular devices arranged side by being fixed from the rear to a horizontally arranged support rail.

The upper surface 14 has two lead-in

holes

20 and 21, respectively leading to a connection terminal 22 and a connection terminal 23. The introduction hole 20 and the terminal 22 are located on the left side. The introduction hole 21 and the terminal 23 are located on the right side.

Likewise, the lower face 16 has two lead-in holes, a first hole and a second hole giving access to the connection terminal 26 and the connection terminal 27, respectively. The first introduction hole and the terminal 26 are located on the left side. The second introduction hole and the terminal 27 are located on the right side.

Each

connection terminal

22,23, 26 and 27 is designed to receive a bare end portion of a cable or a tooth of a horizontally distributed comb, the pitch of which (the central distance between two consecutive teeth) is the modulus.

Here, the

terminals

22 and 23 located at the top are designed for connection to two poles of the power distribution network, while the two

terminals

26 and 27 located at the bottom are designed for connection to the circuit of the electrical apparatus to be protected.

The device 10 is a differential circuit breaker having protected poles, that is, a circuit for detecting short circuits and overcurrent in a transmission circuit of the protected poles (circuit breaker function) and a circuit for detecting a difference in intensity of current flowing in the transmission circuit of the protected poles and a transmission circuit of an unprotected pole (differential function).

The

terminals

22 and 26 on the left are designed here for the poles of the electrical device to be protected, which is a phase, while the

terminals

23 and 27 on the right are designed for the poles of the unprotected electrical device, which is neutral.

The current carrying circuit between the left-

hand terminals

22 and 26 comprises, in series, a magnetic breaking element 30, a fixed contact 31, a movable contact 32, a thermal breaking element 33 and a winding 34 forming part of a differential fault detection transformer 35.

The current carrying circuit between the

terminals

23 and 27 on the right comprises, in series, a fixed contact 36, a movable contact 37 and a winding 38 forming part of a differential fault detection transformer 35.

The transformer 35 comprises, in addition to a winding 34 constituting a current carrying circuit between the

terminals

22 and 26 on the left of the primary winding and a winding 38 constituting a current carrying circuit between the

terminals

23 and 27 on the right, a secondary winding 39, and a toroidal armature (magnetic circuit) 40 around which the secondary winding 39 and the

primary windings

34 and 38 are implemented.

The secondary winding 39 of the transformer 35 is connected to an electronic card 43 by two

electrical conductors

41 and 42.

The magnetic disconnection element 30 is part of a compact element 44, the compact element 44 also comprising a protective relay 45. The electronic card 43 is connected on the one hand by two

conductors

28 and 29 to the terminal 22 and the terminal 23 respectively and on the other hand by two

conductors

46 and 47 to the protective relay 45.

To control the

movable contacts

32 and 37, the device 10 includes a mechanism 50, commonly referred to as a latch.

A lever 19 located externally to the device 10 allows manual operation of the lock 50.

The assembly of magnetic breaking element 30, thermal breaking element 33 and protective relay 45 connected to electronic card 43 is configured to act on lock 50 when necessary.

The lock 50 has two stable positions, respectively a disconnected position in which the two

movable contacts

32 and 37 are away from the corresponding

fixed contacts

31 and 36, respectively, and an engaged position in which each of the two

movable contacts

32 and 37 abuts on the corresponding

fixed contact

31 and 36.

A lever 19 projecting from the front surface 15 allows manual operation of the lock 50 to switch from the disengaged position to the engaged position and vice versa.

The magnetic circuit breaker device 30, the thermal circuit breaker device 33 and the protective relay 45 are configured to automatically act on the lock 50 to switch from the engaged position to the disengaged position when a predetermined current delivery condition occurs.

The magnetic breaking device 30 acts on the lock 50 in the event of a short circuit, the thermal breaking device 33 acts in the event of an overcurrent and the protective relay 45 acts in the event of a differential fault.

In practice, the magnetic breaking element 30 is constituted by a coil arranged around the core controlling the striker acting on the lock 50 when a short circuit occurs. The thermal cut-out 33 is formed by a bimetal which deforms in the event of an overcurrent over a long period of time and acts on the lock 50 as a result of its deformation. The protective relay 45, which is part of the compact element 44 together with the magnetic breaking element 30, is constituted by another coil arranged around the same movable core. This further coil is supplied with power by an electronic card 43 which reacts to the voltage supplied by the secondary winding 39 of the transformer 35 in the event of a difference between the current flowing in the winding 34 and the current flowing in the winding 38, that is to say a differential fault. When the protective relay 45 is thus powered, it actuates a movable core that controls the action of a striker on the lock 50 to trigger the switching from the engaged position to the disengaged position.

The embodiment of the device 10 shown in fig. 3 is similar to the embodiment shown in fig. 2, except that it does not include the thermal disconnect element 33, and the protection against long term overcurrent involves a current measurement transformer 202.

The transformer 202 includes a ring armature 203 surrounding the conductive elements of the current carrying circuit between the

terminals

22 and 26, and includes a winding 204 surrounding the ring armature 203.

The winding 204 is connected to the electronic card 43 by two

electrical conductors

205 and 206. The card 43 reacts not only to the voltage supplied by the winding 39 of the transformer 35 but also to the voltage supplied by the winding 204 of the current measuring transformer 202.

Like the thermal break element 33, the transformer 202 is arranged between the movable contact 32 and the terminal 26, but in view of the thermal break element 33 being arranged between the movable contact 32 and the winding 34, the transformer 202 is arranged between the winding 34 and the terminal 26.

In this case, the electronic card 43 reacts not only to the voltage supplied by the secondary winding 39 of the transformer 35, but also to the voltage supplied by the winding 204 of the transformer 202.

In the event of a long overcurrent, the electronic card 43 supplies the protective relay 45, which protective relay 45 drives a movable core which controls a striker made on the lock 50 to trigger the switching from the engaged position to the disengaged position.

Disclosure of Invention

The present invention aims to provide a similar, but more conveniently and economically manufactured, protection device for ac electrical equipment.

The invention provides for this purpose a protection device for an alternating current electrical apparatus, having a first input connection terminal for a first electrode, a second input connection terminal for a second electrode different from the first electrode and an output connection terminal for the first electrode, each connection terminal being configured to receive an exposed end portion of a cable or a tooth of a horizontal distribution comb; the device comprises:

a first current carrying circuit between the first input connection terminal and the output connection terminal, including a fixed contact and a movable contact;

the control mechanism of the movable contact has two stable positions, namely a disconnecting position where the movable contact is far away from the fixed contact and an engaging position where the movable contact is abutted against the fixed contact;

a lever for manually acting on the control mechanism to switch from the off position to the on position or from the on position to the off position;

a compact element comprising a magnetic breaking element constituted by a magnetic breaking coil arranged around a movable core controlling a striker that acts on the control mechanism upon occurrence of a short circuit and constitutes a part of the first current carrying circuit, and a protective relay constituted by a protective relay coil arranged around said movable core, the magnetic breaking coil and the protective relay coil being arranged around each other;

an electronic circuit connected to a protection relay coil, the electronic circuit configured to power the protection relay coil when a predetermined current delivery condition indicative of a long time overcurrent occurs;

characterized in that the electronic circuit comprises a long-time overcurrent detector configured for determining the occurrence of the current delivery condition from a signal occurring at the end of the protective relay coil and for generating a detection signal when the predetermined current delivery condition occurs; and further comprising a switching circuit configured to connect the protection relay coil to the long term overcurrent detector to isolate the protection relay coil from each of said input connection terminals when said detection signal is absent, and to isolate the protection relay coil from the long term overcurrent detector and then connect the protection relay coil to each of said input connection terminals when said detection signal is present.

The present invention is based on the observation that: the protective relay coil can be used to sense the current flowing in the magnetic breaking coil and therefore in the first current circuit, and furthermore this current-sensing function of the protective relay coil does not prevent the protective relay coil from being used to drive the striker comprised by the compact element, once the protective relay coil is supplied with mains voltage to drive the striker, it is first isolated from the long-term overcurrent detector so as not to destroy the latter.

The signal provided by the protection relay coil represents the current flowing in the magnetic breaking coil, since the magnetic breaking coil and the protection relay coil are arranged around each other and thus interact like a winding of a transformer, including that the coupling between the two coils can be made only through the surrounding air in the absence of specific coupling elements such as electromagnetic armatures.

Unlike the prior art device including the above-described device, the device according to the present invention can perform protection against long-term overcurrent by not including a thermal breaking element such as a bimetal and also not including a specific current capturing element such as a current intensity measuring transformer.

The device according to the invention is therefore particularly simple, convenient and economical to manufacture.

According to an advantageous feature:

-the long-time overcurrent detector is realized by an analog-to-digital converter, a calculation unit and an interface arranged between the switching circuit and the converter, the switching circuit connecting the interface to both ends of the protection relay coil when the detection signal is absent and isolating the interface from both ends of the protection relay coil when the detection signal is present, the interface being configured for providing an analog signal to an input port of the converter that is available for the converter and that corresponds to a voltage present between both ends of the protection relay coil;

-the overcurrent detector comprises in the microcontroller: an analog-to-digital converter connected to the analog port and configured to generate a digital value representative of an analog signal provided by the interface, a calculation unit configured to generate a digital value representative of a root mean square value of the intensity of the current flowing in the magnetic shutdown coil from the digital value representative of the analog signal provided by the interface; and a monitoring unit of the root mean square value of the current flowing in the magnetic shutdown coil configured for comparing the digital value representative of the root mean square value of the intensity of the current with a current intensity threshold and generating the detection signal if the current intensity threshold is exceeded during a predetermined time period;

-said microcontroller is furthermore connected to a communication unit and configured to transmit to said communication unit said digital value representative of the root mean square value of the intensity of the current produced by said calculation unit;

-the communication unit is a radio frequency communication unit;

-the switching circuit comprises:

-a first switching element comprising a control connection point and connected on the one hand to the first input connection terminal and on the other hand to the first end of the protection relay coil, allowing, when there is no predetermined signal at said control connection point, a blocking configuration in which the first switching element isolates the first end of the protection relay coil from the first input connection terminal and allowing, when there is said predetermined signal at said control connection point, a switching-on configuration in which the first switching element connects the first end of the protection relay coil to the first input connection terminal;

-a second switching element comprising a control connection point and connected on the one hand to the second input connection terminal and on the other hand to the second end of the protection relay coil, allowing, when there is no predetermined signal at the control connection point, a blocking configuration in which the second switching element isolates the second end of the protection relay coil from the second input connection terminal and allowing, when there is said predetermined signal at the control connection point, a closing configuration in which the second switching element connects the second end of the protection relay coil to the second input connection terminal;

-a third switching element comprising a control connection point and being connected on the one hand to the first end of the protection relay coil and on the other hand to the long-term overcurrent detector, a switch-on configuration being allowed when there is no predetermined signal at said control connection point, in which switch-on configuration the first end of the protection relay coil is connected to said long-term overcurrent detector, and a switch-off configuration being allowed when there is said predetermined signal at said control connection point, in which switch-off configuration the first end of the protection relay coil is isolated from said long-term overcurrent detector;

-a fourth switching element comprising a control connection point and being connected on the one hand to the second end of the protection relay coil and on the other hand to the long-term overcurrent detector, a switch-on configuration being allowed when there is no predetermined signal at said control connection point, in which switch-on configuration the second end of the protection relay coil is connected to said long-term overcurrent detector, and a switch-off configuration being allowed when there is said predetermined signal at said control connection point, in which switch-off configuration the second end of the protection relay coil is isolated from said long-term overcurrent detector;

-the long-time overcurrent detector is configured for generating a start signal at the end of a predetermined period of time from the generation of the detection signal, the electronic circuit being configured for applying the detection signal to the control connection point of the third switching element and to the control connection point of the fourth switching element, and for applying the start signal to the control connection point of the first switching element and to the control connection point of the second switching element;

the first switching element and the second switching element each comprise a transistor and a thyristor;

-the third switching element and the fourth switching element each comprise a transistor;

the protection device is in the form of a module, substantially parallelepiped in shape, with two main surfaces, respectively a left surface and a right surface, and a lateral surface extending from one main surface to the other, the width of said lateral surface, that is to say the distance between the left and right surfaces, being equal to an integer multiple of a predetermined distance, called the modulus;

-the ratio of the number of turns of the protective relay coil to the number of turns of the magnetic trip coil is between 100 and 500; and/or

-the device has a second output connection terminal for a second electrode, the output connection terminal being configured for receiving a bare end portion of a cable or teeth of a horizontal distribution comb; the apparatus includes a second current carrying circuit between the second input connection terminal and the second output connection terminal.

Drawings

The introduction of the invention will now be continued by the following description of an embodiment given by way of illustration and not limitation with reference to the accompanying drawings.

FIG. 1, which has been described, is a perspective view of a known protective device, taken from the right, top and front of the device;

fig. 2, already described, very schematically shows the electric circuit of a first embodiment of the known device and the control mechanism of the movable contacts that it comprises;

fig. 3, already described, very schematically shows an electric circuit of a second embodiment of the known device and a control mechanism of the movable contacts comprised by the electric circuit;

fig. 4 shows, in a similar way to fig. 2 and 3, the circuit of the device according to the invention and the control mechanism of the movable contacts that it comprises;

FIG. 5 is a schematic diagram of an electronic circuit included in the circuit of FIG. 4;

fig. 6 shows in detail the first switching element and the second switching element of the electronic circuit shown in fig. 5;

FIG. 7 shows in detail the third switching element and the fourth switching element of the electronic circuit of FIG. 5;

FIG. 8 shows in detail the interfaces comprised by the electronic circuit shown in FIG. 5;

fig. 9 is a flow chart showing the operation of a monitoring unit implemented in a microcontroller comprised in the electronic circuit shown in fig. 5;

FIG. 10 is an exploded view of the compact components and electromechanical connections that the device comprises;

FIG. 11 is a perspective view of the compact component and the connector;

FIG. 12 is an elevational cross-section of the compact component and the connector;

FIG. 13 is a left side sectional view of the device according to the present invention with the left side panel of the housing removed;

FIG. 14 is a view similar to FIG. 13, but taken from the right;

fig. 15 shows, in a similar way to fig. 4, a variant of the circuit of the device according to the invention and the control mechanism of the movable contacts which the circuit comprises; and

fig. 16 is a schematic diagram of an electronic circuit included in the circuit of fig. 15.

Detailed Description

In the usual manner, the protection device 100 of an alternating current electrical apparatus is similar to the device 10 described with reference to fig. 1 and 2, except that it does not comprise the thermal disconnection element 33 and does not comprise the differential fault detection transformer 35, and the electronic card 43 is replaced by an electronic circuit 43a and the electronic circuit 43a is connected by a conductor 48 to a first current-carrying circuit between the movable contact 32 and the connection terminal 26 and by a conductor 49 to a second current-carrying circuit between the movable contact 37 and the connection terminal 27.

For simplicity, we have retained the same numerical reference numbers for the device 100 for similar elements as the device 10.

The device 100 comprises a first input connection terminal 22 for a first electrode, a second input connection terminal 23 for a second electrode different from the first electrode, a first output connection terminal 26 for the first electrode and a second output connection terminal 27 for the second electrode.

Each of the

connection terminals

22,23, 26, 27 is configured to receive an exposed end portion of a cable or a tooth of a horizontal distribution comb.

As shown in fig. 4, the apparatus 100 includes a first current carrying circuit between the first input connection terminal 22 and the first output connection terminal 26.

The first current carrying circuit includes a fixed contact 31 and a movable contact 32.

The device 100 furthermore comprises a second current supply circuit between the second input connection terminal 23 and the second output connection terminal 27.

The second current carrying circuit includes a fixed contact 36 and a movable contact 37.

The control mechanism 50 of the

movable contacts

32 and 37 has two stable positions, respectively an open position and an engaged position.

In the open position, the movable contact 32 is away from the fixed contact 31 and the movable contact 37 is away from the fixed contact 36.

In the engaged position, the movable contact 32 abuts against the fixed contact 31 and the movable contact 37 abuts against the fixed contact 36.

The device 100 comprises a lever 19 configured for manual manipulation of the operating mechanism 50 for switching from the disengaged position to the engaged position or vice versa.

The protection device 100 comprises a compact element 44.

The compact element 44 comprises a magnetic breaking element 30 and a protective relay 45.

The compact element 44 is configured to act on the lock 50 to switch from the engaged position to the disengaged position in the event of a short circuit or a long overcurrent.

As shown in fig. 10 to 14, the magnetic breaking element 30 is constituted by a magnetic breaking coil 51 arranged around a movable core 103 which controls a striker 102 to act on the control mechanism 50 when a short circuit occurs.

The magnetic breaker coil 51 constitutes a part of the first current carrying circuit. The magnetic breaking coil 51 is located between the input connection terminal 22 and the fixed contact 31.

The protective relay 45 is constituted by a protective relay coil 52 arranged around the movable core 103.

The protective relay coil 52 is provided with a first end portion 110 and a second end portion 110 a.

The magnetic breaking coil 51 and the protective relay coil 52 are arranged around each other.

Here, the magnetic breaking coil 51 is arranged around the protective relay coil 52.

The fact that the two windings constituting the coil 51 and the coil 52 are arranged around each other creates a transformer effect, that is to say that the current flowing in the coil 51 induces a current in the coil 52 due to the electromagnetic coupling of the two coils through the air.

The transformation ratio is the ratio between the number of turns of the two windings.

Here, the coil winding of the protective relay 52 has two thousand turns, and the magnetic opening coil 51 has five turns, so that the transformation ratio is 400.

Generally, it is advantageous that the ratio of the number of turns of the protective relay coil 52 to the number of turns of the magnetic breaking coil 51 is comprised between 100 and 500.

In fact, in this range, it is easy to have a suitable number of turns, for example, 1000 to 1500 turns, which allows the protective relay coil to function as both the sensor and the actuator, and a suitable number of turns, for example, 3 to 10 turns, which allows the magnetic breaking coil to function as both the protective relay coil and the actuator.

The electronic circuit 43a of the device 100 is connected to the protective relay coil 52 by

conductors

46 and 47.

More specifically, as shown in fig. 6, conductor 46 is connected to terminal 110 and conductor 47 is connected to terminal 110 a.

The electronic circuit 43a is configured to power the protective relay coil 52 when a predetermined current delivery circuit condition indicative of a long time overcurrent occurs.

As can be seen in fig. 5, the electronic circuit 43a comprises a long-time overcurrent detector 60 and a switching circuit 61.

The long-time overcurrent detector 60 is configured to determine the presence of a current delivery condition indicative of a long-time overcurrent from the signals appearing at the

ends

110 and 110a of the protective relay coil 52.

The long-time overcurrent detector 60 is furthermore configured to generate a detection signal when a predetermined current delivery condition exists, i.e. in the case of a long-time overcurrent, and subsequently to generate a start signal at the end of a predetermined period of time from the generation of the detection signal.

The long-time overcurrent detector 60 and the switching circuit 61 are configured such that the switching circuit 61 connects the protective relay coil 52 to the long-time overcurrent detector 60 while isolating the protective relay coil 52 from each of the

input connection terminals

22,23 when there is no detection signal.

The switching circuit 61 isolates the protective relay coil 52 from the long-time overcurrent detector 60 when the detection signal is present, and then subsequently connects the protective relay coil 52 to each of the

input connection terminals

22 and 23 when the start signal is present.

The long term overcurrent detector 60 is implemented by a microcontroller 95 and an interface 70.

An interface 70 is provided between the switching circuit 61 and the analogue input port 67 of the microcontroller 95.

The switching circuit 61 connects the interface 70 to both

end portions

110 and 110a of the protection relay coil 52 when there is no detection signal and isolates the interface 70 from both

end portions

110 and 110a of the relay coil 52 when a detection signal occurs.

The interface 70 has two input connection points 74 and 75 which the switching circuit 61 connects or does not connect to the

ends

110 and 110a of the coil 52, respectively, and the output connection point 76 is connected to the analogue input port 67 of the microcontroller 95.

As can be seen in fig. 5, the input connection point 75 is connected to the reference pole of the dc part of the electronic circuit 43 a. Thus, when the switching circuit 61 connects the input connection point 75 to the end 110a of the coil 52, this end is brought to this reference pole.

The interface 70 is configured to provide an analog signal to the analog input port 67 that is usable by the microcontroller 95 and that corresponds to the voltage present between the two ends 110 and 110a of the protective relay coil 52.

As shown in fig. 8, the interface 70 includes an amplifier 114 having an output connected to the output connection point 76. Between the input connection point 74 and the + input of the amplifier 114, two

resistors

116 and 117 are arranged in series. Between the reference pole, to which the input connection point 75 is connected, and the-input of the amplifier 114, a resistor 118 is placed. The capacitor 115 is arranged between the input connection point 75 and one side of the

resistors

116 and 117 connected to each other. A resistor 119 is arranged between the output of the amplifier 114 and its-input. The

resistors

120 and 121 are connected to each other. The + input of amplifier 114 is connected to one side of

resistors

120 and 121, which are connected to each other. The other sides of the

resistors

120 and 121 are connected to the + and reference poles, respectively, of the power supply of the electronic circuit 43 a.

Resistor 116 and capacitor 115 allow the current flowing through coil 52 to be converted to a voltage and low pass filtering to be performed.

Resistors

117, 120, and 121 allow amplifier 114 to polarize.

Resistors

118 and 119 allow the gain of amplifier 114 to be fixed.

The long-time overcurrent detector 60 includes a converter 71, a calculation unit 72, and a monitoring unit 73 in a microcontroller 95.

The converter 71 is connected to the analog port 67 of the microcontroller 95 and is configured to generate a digital value representative of the analog signal provided by the interface 70.

The calculation unit 72 is configured to generate, from the digital values representing the analog signals provided by the interface 70, digital values representing the root mean square value of the intensity of the current flowing in the magnetic shutdown coil 51.

In practice, the calculation unit 72 is implemented by conventional techniques for calculating the root mean square value of the sinusoidal signal and by calibration.

As can be seen in fig. 9, the rms value monitoring unit 73 of the current flowing in the magnetic shutdown coil 51 is configured to compare the digital value I representing the rms value of the current intensity with a current intensity threshold value "threshold value I" and to generate a detection signal if this threshold value is exceeded during a predetermined time period "threshold value t".

The monitoring unit 73 here conforms to the french standard NF C15-100, largely in accordance with the european standard HD 384, describing the breaking time of the circuit breaker, but using the bimetallic strip technique.

The monitoring unit 73 must not generate a detection signal when the value of the root mean square value I representing the intensity of the current is less than or equal to 1.13 times the current intensity threshold value in a time less than one hour.

The monitoring unit 73 should generate a detection signal within one hour when the value of the root mean square value I representing the intensity of the current is greater than or equal to 1.45 times the current intensity threshold value.

As a variant, the monitoring unit 73 satisfies a single criterion, for example, when the value of the root mean square value I representative of the intensity of the current is equal to 1.2 times the current intensity threshold, the monitoring unit 73 generates a detection signal within a few milliseconds, allowing the disconnection of the device.

The detection signal generated by the monitoring unit 73 is available on port 68 of the microcontroller 95.

At the end of a predetermined period of time after the start of the generation of the detection signal, the monitoring unit 73 also generates an activation signal available on the port 69 of the microcontroller 95.

The predetermined time is between 1 and 10 milliseconds depending on the assembly used and its reaction time.

The microcontroller 95 also comprises a port 66 on which the values generated by the calculation unit 72 can be used.

The port 66 is connected to a communication element 96, here a radio frequency, to which the value generated by the calculation unit 72, i.e. a value representative of the root mean square value of the intensity of the current flowing in the magnetic shutdown coil 51, is therefore transmitted. That is to say the current is the current flowing in the electrical device or part of the electrical device located between the

output terminals

26 and 27 of the apparatus 100.

The radio frequency communication element 96 allows this current or a value derived therefrom, in particular the power consumption of a device or a part of a device located between the

output terminals

26 and 27 of the apparatus 100, to be tracked remotely, for example via a mobile application. For example, the device 100 communicates with a gateway so that current consumption information can be found on the cloud accessed by the mobile application.

As a variant, the radio frequency communication element 96 is replaced by a different communication element, for example wired or infrared, and the device 100 is equipped with a corresponding port.

The switching circuit 61 includes a first switching element 79, a second switching element 80, a third switching element 81, and a fourth switching element 82.

The first switching element 79 comprises a control connection point 87, a first connection point 83 connected to the output connection terminal 26 by means of the conductor 48 and the trace of the electronic circuit 43a, and a second connection point 84 connected to the first end 110 of the protective relay coil 52 by means of the conductor 46 and the trace of the electronic circuit 43a (fig. 6).

In the absence of the predetermined signal at the control connection point 87, the first switching element 79 assumes a blocking configuration in which the first end 110 of the protective relay coil 52 is isolated from the output connection terminal 26.

The control connection point 87 is connected via a trace of the electronic circuit 43a to the port 69 of the microcontroller 95, on which the start signal is present or not.

In the presence of a predetermined signal at the control connection point 87, in the case of a start signal, the first switching element 79 allows to switch on the configuration in which the first end 110 of the protective relay coil 52 is connected to the output connection terminal 26.

In the blocking configuration, the first connection point 83 is isolated from the second connection point 84 and in the pass-through configuration, the first connection point 83 is connected to the second connection point 84.

As seen in fig. 6, the first switching element 79 includes a transistor 97 and a thyristor 98.

The control connection point 87 is connected to the base of a transistor 97 whose collector is connected to the + supply pole of the electronic circuit 43a and whose emitter is connected to one side of a first resistor and a second resistor, the other side of the first resistor being connected to the reference pole of the supply and the other side of the second resistor being connected to the gate of a thyristor 98, the anode of which is connected to the first connection point 83 and the cathode of which is connected to the second connection point 84.

In the absence of a start signal at connection 87, transistor 97 is blocked, as is thyristor 98.

When there is a start signal at connection 87, transistor 97 conducts between its collector and its emitter, causing a signal to appear at the gate of thyristor 98, which conducts between its anode and its cathode.

The second switching element 80 comprises a control connection point 88, a first connection point 85 connected to the second output connection terminal 27 via the conductor 49 and the trace of the electronic circuit 43a, and a second connection point 86 connected to the second end 110a of the protective relay coil 52 via the conductor 47 and the trace of the electronic circuit 43a (fig. 6).

In the absence of the predetermined signal at the control connection point 88, the second switching element 80 allows a blocking configuration in which the second end 110a of the protective relay coil 52 is isolated from the output connection terminal 27.

The control connection point 88 is connected via a trace of the electronic circuit 43a to the port 69 of the microcontroller 95, on which the start signal is present or not.

In the presence of a predetermined signal at the control connection point 88, in the case of a start signal, the second switching element 80 allows a switch-on configuration in which the second end 110a of the protective relay coil 52 is connected to the output connection terminal 27.

In the blocking configuration, the first connection point 85 is isolated from the second connection point 86 and in the closing configuration, the first connection point 85 is connected to the second connection point 86.

As seen in fig. 6, the second power supply switching element 80 includes a transistor 97 and a thyristor 98.

The control connection point 88 is connected to the base of a transistor 97, the collector of the transistor 97 being connected to the supply + pole of the electronic circuit 43a and the emitter thereof being connected to one side of a first resistor and a second resistor, the other side of the first resistor being connected to the reference pole of the supply and the other side of the second resistor being connected to the gate of a thyristor 98, the anode of which being connected to the first connection point 85 and the cathode thereof being connected to the second connection point 86.

In the absence of a start signal at junction 88, transistor 97 is blocked, as is thyristor 98.

When the start signal is present at junction 88, transistor 97 conducts between its collector and its emitter, causing a signal to appear at the gate of thyristor 98, which thyristor 98 becomes conductive between its anode and cathode.

The fact that the thyristor 98 is switched on causes the end of the protection relay coil 52 to switch on the grid voltage, the striker 102 is actuated, and the latch 50 causes the

movable contacts

32 and 37 to move away from the fixed

contacts

31 and 36, which simultaneously isolates the protection relay coil 52 from the grid.

The third switching element 81 comprises a control connection point 93, a first connection point 89 connected to the first end 110 of the protective relay coil 52 by a conductor 46 and a trace of the electronic circuit 43a, and a second connection point 90 connected by a trace of the electronic circuit 43a to the input connection point 74 of the interface 70.

In the absence of the predetermined signal at the control connection point 93, the third switching element 81 allows a switch-on configuration, in which the first end 110 of the protective relay coil 52 is connected to the long-time overcurrent detector 60, here to the input connection point 74.

The control connection 93 is connected by traces of the electronic circuit 43a to the port 68 of the microcontroller 95, on which the detection signal is present or not.

In the presence of a predetermined signal at the control connection point 93, in the case of a detection signal, the third switching element 81 assumes a blocking configuration in which the first end 110 of the protective relay coil 52 is isolated from the long-term overcurrent detector 60.

In the on configuration, the first connection point 89 is connected to the second connection point 90, and in the off configuration, the first connection point 89 is isolated from the second connection point 90.

As seen in fig. 7, the third switching element 81 includes a transistor 99.

The control connection point 93 is connected to one side of a first resistor and one side of a second resistor, the other side of the first resistor being connected to the reference of the power supply and the other side of the second resistor being connected to the base of the transistor 99. Connection point 89 is connected to the collector of transistor 99 and connection point 90 is connected to the emitter of transistor 99.

In the absence of the detection signal at the connection point 93, the transistor 99 is turned on, and the absence of the detection signal is at a high voltage level at the connection point 93.

Transistor 99 is blocked when a detection signal is present at connection point 93, the presence detection signal being a low voltage level at connection point 93.

The fourth switching element 82 comprises a control connection point 94, a first connection point 91 connected to the second end 110a of the protective relay coil 52 via the conductor 47 and the trace of the electronic circuit 43a, and a second connection point 92 connected to the input connection point 75 of the interface 70 via the trace of the electronic circuit 43 a.

In the absence of the predetermined signal at the control connection point 94, the fourth switching element 82 allows a switch-on configuration, in which the second end 110a of the protective relay coil 52 is connected to the long-time overcurrent detector 60, here to the input connection point 75.

The control connection point 94 is connected to the port 68 of the microcontroller 95 via a trace of the electronic circuit 43a, on which the detection signal is present or not.

In the presence of a predetermined signal at the control connection point 94, in the case of a detection signal, the fourth switching element 82 allows a blocking configuration in which the second end 110a of the protective relay coil 52 is isolated from the long-term overcurrent detector 60.

In the closed configuration, the first connection point 91 is connected to the second connection point 92, while in the blocked configuration, the first connection point 91 is isolated from the second connection point 92.

As seen in fig. 7, the fourth switching element 82 includes a transistor 99.

The control connection 94 is connected to one side of a first resistor and one side of a second resistor, the other side of the first resistor being connected to the reference of the power supply and the other side of the second resistor being connected to the base of the transistor 99. The connection point 91 is connected to the collector of the transistor 99 and the connection point 92 is connected to the emitter of the transistor 99.

In the absence of a detection signal at the connection point 94, the transistor 99 is turned on.

When the detection signal is present at the connection point 94, the transistor 99 is blocked.

As seen in fig. 10 to 12, the compact element 44 comprises, in addition to the magnetic breaking coil 51, the protective relay coil 52, the striker 102 and the movable core 103, a bobbin 101, a guide 107, a spring 108, an insulating sheath 111 and connecting

bars

125 and 125a, here as

conductors

46 and 47.

The protective relay coil 52 is wound on a bobbin 101 of insulating plastic material, the bobbin 101 being generally tubular with a flange visible at the bottom end in the figure and a flange visible at its top that engages with the bays, each bay being for one of the ends of the coil 52 and one of the connecting

rods

125 and 125 a.

An insulating sheath 111 is disposed between the magnetic breaking coil 51 and the protective relay coil 52.

The core 103, the striker 102, the spring 108 and the guide 107 are accommodated in the inner space of the bobbin 101.

The core 103 is generally cylindrical. The housing 104 is disposed in one of its ends. The core 103 is slidably mounted in the bobbin 101.

The guide 107 is fixedly mounted on one end of the bobbin 101. A through hole 113 is provided in the guide 107.

The striker 102 is formed of a rod-shaped main body 106 and a head 105 located at and protruding from one end of the rod.

The cabin 104 is arranged to receive the head 105 of the striker 102. The bore 113 of the guide 107 is arranged to receive the rod 106.

A spring 108 is disposed around the shaft 106 of the striker 102.

The connection rod 125 is arranged between the end 110 of the protective relay coil 52 and the electronic circuit 43a (see in particular fig. 13). Likewise, the connection rod 125a is arranged between the end 110a of the protective relay coil 52 and the electronic circuit 43 a.

Mechanical and electrical connections 112 made of a relatively rigid electrically conductive material are used to mount the compact element 44 on the housing of the device 100 and to realize the electrical connection between the magnetic interruption coil 51 and the fixed contacts 31.

If any fault (long overcurrent or short circuit) does not occur, the core 103 is held away from the guide 107 by the spring 108.

When a fault occurs, the magnetic flux generated by the

coil

51 or 52 acts on the core 103, driving it to slide in the hole 113 against the spring 108 towards the guide 107, by extending its rod 106, which then acts on the control mechanism 50 to drive the striker 102.

When the magnetic flux ceases, the spring 108, core 103 and striker 102 return to the initial position shown in fig. 12.

As shown in fig. 13 and 14, the compact element 44 and the lock 50 straddle the insulating spacer 109. The spacer 109 is provided between the circuit of the protected pole (between terminals 22 and 26) and the circuit of the unprotected pole (between terminals 23 and 27).

In the variant shown in fig. 15, the device 100 furthermore comprises a differential fault detection transformer 35, the electronic circuit 43a being replaced by an electronic circuit 43d, and furthermore the assembly constituted by the protective relay 45 connected to the electronic circuit 43d is also configured to act on the lock 50 not only in the event of long overcurrents but also in the event of differential faults.

In this variant, the current-carrying circuit between the

terminals

22 and 26 comprises, in series, a magnetic breaking element 30, a fixed contact 31, a movable contact 32 and a winding 34 constituting a transformer 35, and the current-carrying circuit between the

terminals

23 and 27 comprises, in series, a fixed contact 36, a movable contact 37 and a winding 38 constituting a differential fault detection transformer 35.

The transformer 35, in addition to the winding 34 and the winding 38, includes a secondary winding 39 and a ring armature 40 around which the secondary winding 39 and the

primary windings

34 and 38 are formed.

The secondary winding 39 is connected by two

conductors

41, 42 to an electronic circuit 43d, which electronic circuit 43d processes, in addition to the signal representing the current intensity supplied by the coil 52, the differential fault signal supplied by the transformer 35.

In general, the electronic circuit 43d is similar to the electronic circuit 43a, except that the long-term overcurrent detector 60 is replaced by an assembly of an interface 70, a converter 71, a calculation unit 72, a monitoring unit 73 for determining the root mean square value of the intensity of the current flowing in the magnetic trip coil 51; and in addition to it comprises a switching interface 63 which generates a signal to which the switching circuit 61 is responsive.

The switching interface 63 comprises two

connection points

170 and 171 connected to the secondary winding 39 of the transformer 35 by

conductors

42 and 41, respectively, and two output connection points 168 and 169, respectively, connected to the switching circuit 61.

More precisely, the output connection point 168 is connected to the control connection points 93 and 94 of the third switching element 81 and the fourth switching element 82, respectively; and the output connection point 169 is connected to the control connection points 87 and 88 of the first switching element 79 and the second switching element 80, respectively.

When the transformer 35 provides a differential fault signal on the

conductors

41 and 42, the interface 63 responsively generates a detection signal that is transmitted to the third switching element 81 and the fourth switching element 82, and then generates an activation signal that is transmitted to the first switching element 79 and the second switching element 80.

In a variant not shown:

the protective relay coil 52 is arranged around the magnetic breaking coil 51 and not vice versa;

the implementation of the switching circuit differs from the embodiments shown in fig. 6 and 7, for example by using optocouplers instead of transistors and thyristors;

the implementation of the long-term overcurrent detector differs from the embodiments shown in fig. 5, 8 and 9, for example in a completely analog manner;

the start signal generated at the end of a predetermined period of time after the generation of said detection signal is not provided by a long-time overcurrent detector, for example by a switching circuit similar to circuit 61, but is configured to receive only the detection signal;

the current carrying circuit of the protected pole is on the right instead of the left, and the current carrying circuit of the unprotected pole is on the left instead of the right; and/or

The protection device does not comprise the second output connection terminal 27 for the second electrode and therefore does not comprise the second current carrying circuit between

terminals

23 and 27.

In a variant not shown, the protection device has a different width and/or a different number of poles, for example a quadrupole device with a width of four modules, comprising four terminals in the upper part and four terminals in the lower part.

More generally, the invention is not limited to the examples described and shown.

Claims

1. A protection device for an alternating current electrical apparatus having a first input connection terminal (22) for a first electrode, a second input connection terminal (23) for a second electrode different from the first electrode and an output connection terminal (26) for the first electrode, each connection terminal (22,23, 26) being configured to receive a bare end portion of a cable or a tooth of a horizontally distributed comb; the device comprises:

a first current carrying circuit between the first input connection terminal (22) and the output connection terminal (26), comprising a fixed contact (31) and a movable contact (32);

a control mechanism (50) of the movable contact (32) having two stable positions, respectively a disconnection position where the movable contact (32) is away from the fixed contact (31) and an engagement position where the movable contact (32) abuts on the fixed contact (31);

a lever (19) for manual action on the control mechanism (50) in order to switch from the disengaged position to the engaged position or vice versa;

a compact element (44) comprising a magnetic breaking element (30) and a protective relay (45), said magnetic breaking element (30) being constituted by a magnetic breaking coil arranged around a movable core controlling a striker which acts on a control mechanism (50) when a short circuit occurs and constitutes a part of a first current carrying circuit, said protective relay (45) being constituted by a protective relay coil arranged around said movable core, the magnetic breaking coil and the protective relay coil being arranged around each other;

characterized in that the electronic circuit (43a, 43d) comprises a long-time overcurrent detector (60), the long-time overcurrent detector (60) being configured for determining the occurrence of the current delivery condition from a signal occurring at an end (110, 110a) of the protective relay coil (52) and for generating a detection signal when the predetermined current delivery condition occurs; and further comprising a switching circuit (61), said long term overcurrent detector (60) and said switching circuit (61) being configured to connect the protective relay coil (52) to the long term overcurrent detector (60) to isolate the protective relay coil (52) from each of said input connection terminals (22,23) when said detection signal is absent, and to isolate the protective relay coil (52) from the long term overcurrent detector (60) and then connect the protective relay coil (52) to each of said input connection terminals (22,23) when said detection signal is present.

2. Protection device according to claim 1, characterized in that the long time overcurrent detector (60) is realized by an analog-to-digital converter (71), a calculation unit (72) and an interface (70) arranged between the switching circuit (61) and the converter (71), the switching circuit (61) connects an interface (70) to both ends (110, 110a) of a protective relay coil (52) when the detection signal is absent, and isolating the interface (70) from both ends (110, 110a) of the protective relay coil (52) when the detection signal is present, the interface (70) is configured for providing an input port of a converter (71) with an analog signal available to the converter (71) and corresponding to a voltage present between two ends (110, 110a) of the protective relay coil (52).

3. Protection device according to claim 2, characterized in that the long time overcurrent detector (60) comprises in the microcontroller (95): an analog-to-digital converter (71) connected to the analog port (67) and configured for generating a digital value representative of an analog signal provided by the interface (70), a calculation unit configured for generating a digital value representative of a root mean square value of the intensity of the current flowing in the magnetic trip coil (51) from the digital value representative of an analog signal provided by the interface (70); and a monitoring unit (73) of the root mean square value of the current flowing in the magnetic disconnection coil (51), configured for comparing the digital value representative of the root mean square value of the intensity of the current with a current intensity threshold and generating the detection signal if the current intensity threshold is exceeded during a predetermined time period.

4. Protection device according to claim 3, characterized in that said microcontroller (95) is also connected to a communication element (96) and is configured for transmitting to said communication element (96) said digital value representative of the root mean square value of the intensity of the current generated by said calculation unit (72).

5. The protection device according to claim 4, characterized in that the communication element (96) is a radio frequency communication element.

6. Protection device according to any one of claims 1 to 5, characterized in that said switching circuit (61) comprises:

-a first switching element (79) comprising a control connection point (87) and connected on the one hand to the first input connection terminal (22) and on the other hand to the first end (110) of the protection relay coil (52), a blocking configuration being allowed when there is no predetermined signal at said control connection point (87), in which blocking configuration the first switching element (79) isolates the first end (110) of the protection relay coil (52) from the first input connection terminal (22) and an on configuration being allowed when there is said predetermined signal at said control connection point (87), in which on configuration the first switching element (79) connects the first end (110) of the protection relay coil (52) to the first input connection terminal (22);

-a second switching element (80) comprising a control connection point (88) and connected on the one hand to the second input connection terminal (23) and on the other hand to the second end (110a) of the protection relay coil (52), allowing a blocking configuration when there is no predetermined signal at the control connection point (88), in which blocking configuration the second switching element (80) isolates the second end (110a) of the protection relay coil (52) from the second input connection terminal (23), and allowing a switching-on configuration when there is the predetermined signal at the control connection point (88), in which switching-on configuration the second switching element (80) connects the second end (110a) of the protection relay coil (52) to the second input connection terminal (23);

-a third switching element (81) comprising a control connection point (93) and connected on the one hand to a first end (110) of a protection relay coil (52) and on the other hand to a long-term overcurrent detector (60), a switch-on configuration being allowed when there is no predetermined signal at said control connection point (93), in which switch-on configuration the first end (110) of the protection relay coil (52) is connected to said long-term overcurrent detector (60), and a switch-off configuration being allowed when there is said predetermined signal at said control connection point (93), in which switch-off configuration the first end (110) of the protection relay coil (52) is isolated from said long-term overcurrent detector (60);

-a fourth switching element (82) comprising a control connection point (94) and connected on the one hand to the second end (110a) of the protection relay coil (52) and on the other hand to the long-time overcurrent detector (60), an on configuration being allowed when there is no predetermined signal at said control connection point (94), in which the second end (110a) of the protection relay coil (52) is connected to said long-time overcurrent detector (60), and a blocking configuration being allowed when there is said predetermined signal at said control connection point (94), in which the second end (110a) of the protection relay coil (52) is isolated from said long-time overcurrent detector (60).

7. A protection device according to claim 6, characterized in that the long time overcurrent detector (60) is configured for generating a start signal at the end of a predetermined period of time from the generation of the detection signal, the electronic circuit (43a, 43d) being configured for applying the detection signal to the control connection point (93) of the third switching element (81) and to the control connection point (94) of the fourth switching element (82), and for applying the start signal to the control connection point (87) of the first switching element (79) and to the control connection point (88) of the second switching element (80).

8. A protection device according to claim 6 or 7, characterized in that the first switching element (79) and the second switching element (80) each comprise a transistor (97) and a thyristor (98).

9. A protection device according to claim 6 or 7, characterized in that the third switching element (81) and the fourth switching element (82) each comprise a transistor (99).

10. Protection device according to any one of claims 1 to 9, characterized in that it is in the form of a module, substantially parallelepiped-shaped, with two main surfaces (11, 12), respectively a left surface (11) and a right surface (12), and a lateral surface extending from one main surface to the other, the width of said lateral surface, that is to say the distance between the left surface (11) and the right surface (12), being equal to an integer multiple of a predetermined distance, called the modulus.

11. Protection device according to any of claims 1 to 10, characterized in that the ratio between the number of turns of the protection relay coil (52) and the number of turns of the magnetic breaking coil (51) is comprised between 100 and 500.

12. Protection device according to any one of claims 1 to 11, characterized in that it has a second output connection terminal (27) for a second electrode, said output connection terminal (27) being configured for receiving a bare end portion of a cable or the teeth of a horizontal distribution comb; the device comprises a second current carrying circuit between the second input connection terminal (23) and the second output connection terminal (27).