EP3288059B1 - Commandable trip unit for an electrical circuit breaker - Google Patents

Description

The present invention relates to a controllable trigger for an electric circuit breaker. The invention also relates to an electrical apparatus comprising an electric circuit breaker and such a trigger associated with this electric circuit breaker. The invention finally relates to a method of operating such a trigger.

In known manner, a trigger for an electric circuit breaker has the function of opening the circuit breaker with which it is associated, so as to interrupt the flow of an electric current between input and output terminals of the circuit breaker, when the trip unit receives a dedicated command signal. For example, this control signal is issued by an operator by pressing an emergency stop button. The purpose of the release is to open the circuit breaker as soon as possible after receiving this control signal, even if a control circuit integrated in the circuit breaker has not detected any malfunction of the circuit breaker. It is therefore essential that the trigger provided by the trigger is made as quickly and reliably as possible.

Mechanically latching releases are known, which are intended to be mechanically coupled to a switching mechanism of the circuit breaker. Typically, these triggers include a motorized actuator to move and hold a breaker switch mechanism in place to open the circuit breaker.

A disadvantage of these known triggers is that they dissipate significant energy in thermal form during their operation, due to the power supply requirements of the motorized actuator. Another disadvantage is that it is necessary to continuously power the motorized actuator to maintain the switching mechanism in the open state. This generates a significant power consumption, and therefore heat dissipation also important. Such heat dissipation is undesirable because it causes the trigger to heat up, which can affect its operation. In addition, such heating is particularly detrimental in cases where it is desired to miniaturize the trigger or in cases where the trigger is used in a constrained environment.

The patent application EP-1209712-A1 discloses an example of a known circuit breaker having the features of the preamble of claim 1. Furthermore, this document discloses a method of controlling such a trigger, this method comprising steps of providing the trigger and acquiring a trigger. Trigger command signal from the trigger.

It is to these drawbacks that the invention more particularly intends to remedy by proposing a controllable trigger for an electric circuit breaker, which has a reduced thermal energy dissipation during its operation.

• un actionneur , comprenant un organe de couplage déplaçable entre une position de repos et une position déclenchée, l'organe de couplage étant destiné à être couplé mécaniquement à un mécanisme de commutation d'un disjoncteur électrique pour entraîner la commutation du disjoncteur depuis un état fermé vers un état ouvert lorsque l'organe de couplage passe de la position de repos vers la position déclenchée, et
• un dispositif de commande, configuré pour alimenter l'actionneur en réponse à la réception, par le déclencheur, d'un signal de commande de déclenchement, pour déplacer l'organe de couplage de la position de repos vers la position déclenchée.

L'actionneur est un actionneur magnétique comportant une bobine configurée pour déplacer l'organe de couplage depuis la position de repos vers la position déclenchée lorsqu'elle est alimentée avec une impulsion d'un courant électrique d'intensité supérieure à un premier seuil prédéfini pendant une durée supérieure ou égale à une durée prédéfinie, et le dispositif de commande est configuré pour alimenter électriquement la bobine, dès réception du signal de commande et tant que le signal de commande est maintenu, avec une série d'impulsions de courant électrique de durée égale à la durée prédéfinie et d'intensité supérieure ou égale au premier seuil et inférieure ou égale à un deuxième seuil, ce deuxième seuil étant au plus égal à 120% du premier seuil.The invention therefore relates to a controllable trigger for an electric circuit breaker, the circuit breaker is switchable between an open state and a closed state, this trigger comprises:

• an actuator, comprising a coupling member movable between a rest position and a triggered position, the coupling member being adapted to be mechanically coupled to a switching mechanism of an electric circuit breaker to cause switching of the circuit breaker from a closed state to an open state when the coupling member moves from the rest position to the tripped position, and
• a controller configured to supply the actuator in response to the trigger being received by a trigger control signal to move the coupling member from the home position to the triggered position.

The actuator is a magnetic actuator having a coil configured to move the coupling member from the home position to the triggered position when energized with a pulse of an electrical current of greater magnitude than a first predetermined threshold for a duration greater than or equal to a predefined duration, and the control device is configured to electrically supply the coil, upon receipt of the control signal and as long as the control signal is maintained, with a series of pulses of electric current of duration equal to the predefined duration and of intensity greater than or equal to the first threshold and less than or equal to a second threshold, this second threshold being at most equal to 120% of the first threshold.

Thanks to the invention, by using such a magnetic actuator, the displacement of the coupling member to its tripped position requires only a small amount of energy, provided by the pulse of electric current in the coil. In addition, the circuit breaker lock in the open state is achieved by activating the coil at successive times over time, thanks to the succession of current pulses.

On the contrary, in motorized actuators according to the state of the art, it is necessary to supply a power supply at all times in order to trigger the switching of the circuit breaker to the open state and to keep it locked in the open state, which consumes more energy.

Finally, the limitation of the intensity of the current pulses to a value of intensity lower than the second predefined threshold makes it possible not to supply too much energy to the coil and to limit the amount of energy that is supplied to the coil. the amount of energy required to release the coupling member to the triggered position.

Because the power consumption is reduced compared to known triggers, the amount of energy that is dissipated by the trigger in thermal form is actually reduced.

• Le signal de commande est une tension électrique, reçue sur une entrée du déclencheur, le dispositif de commande étant adapté pour être alimenté électriquement par le signal de commande, et le dispositif de commande comporte :
• une source de tension régulée limitée en courant, connectée en série avec la bobine entre l'entrée et une masse électrique du dispositif de commande, cette source de tension régulée limitée en courant étant configurée pour délivrer une tension d'alimentation sur un rail d'alimentation dès qu'elle est alimentée par le signal de commande,
• un module d'excitation, configuré pour être alimenté électriquement par la tension d'alimentation et pour commander la génération des impulsions de courant électrique,

la source de tension régulée limitée en courant étant en outre configurée pour sélectivement injecter dans la bobine un courant électrique d'intensité égale au deuxième seuil prédéterminé et, en alternance, interrompre la circulation de ce courant électrique, en réponse à des ordres de déclenchement et d'interruption générés par le module d'excitation ;

• Le dispositif de commande comporte une sonde de mesure du courant qui circule au travers de la bobine, et le module d'excitation est programmé pour, successivement, activer puis inhiber l'injection du courant électrique par la source de tension régulée limitée en courant, pour générer chaque impulsion de courant électrique, le module d'excitation étant programmé pour commander cette inhibition à l'expiration du délai prédéterminé, ce délai étant décompté par le module d'excitation, à partir de l'instant où le courant mesuré par la sonde de mesure dépasse la première valeur seuil ;

Selon des aspects avantageux mais non obligatoires de l'invention, un tel déclencheur peut comporter une ou plusieurs des caractéristiques suivantes, prises dans toute combinaison techniquement admissible dans le cadre des revendications ci-jointes :

• Le dispositif de commande comporte un interrupteur commandable, connecté en série avec la bobine et la source de tension régulée limitée en courant entre l'entrée et la masse électrique, la commande de la source étant réalisée par le module d'excitation au moyen de cet interrupteur, l'interrupteur étant à cet effet raccordé au module d'excitation et étant apte à commuter entre un état passant et un état bloquant pour, respectivement, autoriser ou inhiber la circulation du courant électrique, en réponse aux ordres de déclenchement et d'interruption, respectivement, générés par le module d'excitation ;
  • Le module d'excitation est programmé pour détecter si le signal de commande est une tension électrique ou alternative, et pour :
    • synchroniser automatiquement la génération des impulsions de courant électrique avec le signal de commande, si le signal de commande est détecté comme étant une tension électrique alternative, cette synchronisation étant réalisée par le module d'excitation en générant les ordres de déclenchement aux instants où le signal de commande prend une valeur nulle, et, alternativement,
    • commander la génération des impulsions de courant électrique avec une période prédéfinie, si le signal de commande est détecté comme étant une tension électrique continue ;
  • Le module d'excitation est programmé pour commander la génération des impulsions de courant électrique avec un intervalle prédéfini entre deux impulsions de courant électrique consécutives, l'intervalle prédéfini étant inférieur ou égal à 100ms.
  • Le rapport cyclique entre le délai prédéterminé et l'intervalle prédéfini est compris entre $\frac{1}{10}$
    
    et $\frac{1}{100},$
    
    de préférence égal à $\frac{1}{40};$
    
    ;
  • Le dispositif de commande comporte un module d'excitation analogique configuré pour générer, en outre, une unique impulsion de courant électrique, d'intensité supérieure ou égale au premier seuil prédéterminé, dès la réception du signal de commande par le dispositif de commande ;
  • L'actionneur comporte en outre un aimant, une partie mobile reliée mécaniquement à l'organe de couplage et un ressort de déclenchement,

l'aimant étant solidaire d'une partie fixe de l'actionneur et exerçant une force magnétique sur la partie mobile lorsque l'organe de couplage est dans la position de repos, de manière à ce que la partie mobile comprime le ressort pour maintenir l'organe de couplage dans la position de repos, le ressort exerçant une force de rappel s'opposant à la force magnétique, et ayant une intensité inférieure à la force magnétique,
la bobine étant adaptée pour réduire la force d'attraction magnétique exercée par l'aimant lorsqu'elle est alimentée par chacune desdites impulsions du courant électrique appliquées par le dispositif de commande, de manière à autoriser le mouvement de l'organe de couplage de sa position de repos vers la position déclenchée, sous l'effet de la force de rappel exercée par le ressort de déclenchement ;According to the invention, such a trigger has the following characteristics

• The control signal is an electrical voltage, received on a trigger input, the controller being adapted to be electrically powered by the control signal, and the controller includes:
• a current-limited regulated voltage source, connected in series with the coil between the input and an electrical ground of the control device, the current-limited regulated voltage source being configured to supply a supply voltage on a rail of power supply as soon as it is powered by the command signal,
• an excitation module, configured to be electrically powered by the supply voltage and to control the generation of electrical current pulses,

the current-limited regulated voltage source being further configured to selectively inject into the coil an electric current of intensity equal to the second predetermined threshold and, alternately, interrupt the flow of this electric current, in response to trip commands and interrupt generated by the excitation module;

• The control device comprises a current measurement probe which circulates through the coil, and the excitation module is programmed to, successively, activate and then inhibit the injection of the electric current by the regulated voltage source limited in current, to generate each pulse of electric current, the excitation module being programmed to control this inhibition at the expiration of the predetermined delay, this delay being counted by the excitation module, from the instant when the current measured by the measurement probe exceeds the first threshold value;

According to advantageous but non-mandatory aspects of the invention, such a trigger may include one or more of the following features, taken in any technically permissible combination within the scope of the appended claims:

• The control device comprises a controllable switch, connected in series with the coil and the regulated voltage source limited in current between the input and the electrical ground, the control of the source being carried out by the excitation module by means of this switch, the switch being for this purpose connected to the excitation module and being able to switch between an on state and a blocking state to, respectively, allow or inhibit the flow of electric current, in response to the trip commands and interrupt, respectively, generated by the excitation module;
  • The excitation module is programmed to detect whether the control signal is an electrical or alternating voltage, and for:
    • automatically synchronize the generation of the electric current pulses with the control signal, if the control signal is detected as an AC voltage, this synchronization being performed by the excitation module by generating the trip commands at the times when the signal command takes a null value, and, alternatively,
    • controlling the generation of electrical current pulses with a predefined period, if the control signal is detected as a DC voltage;
  • The excitation module is programmed to control the generation of electrical current pulses with a predefined interval between two consecutive electrical current pulses, the predefined interval being less than or equal to 100ms.
  • The duty cycle between the predetermined delay and the predefined interval is between $\frac{1}{10}$
    
    and $\frac{1}{100},$
    
    preferably equal to $\frac{1}{40};$
    
    ;
  • The control device comprises an analog excitation module configured to generate, in addition, a single pulse of electric current of intensity greater than or equal to the first predetermined threshold, on receipt of the control signal by the control device;
  • The actuator further comprises a magnet, a movable part mechanically connected to the coupling member and a trigger spring,

the magnet being secured to a fixed part of the actuator and exerting a magnetic force on the moving part when the coupling member is in the rest position, so that the movable part compresses the spring to maintain the coupling member in the rest position, the spring exerting a restoring force opposing the magnetic force, and having a lower intensity than the magnetic force,
the coil being adapted to reduce the magnetic attraction force exerted by the magnet when powered by each of said pulses of electric current applied by the control device, so as to allow movement of the coupling member from its rest position to the triggered position under the effect of the biasing force exerted by the trigger spring;

• le disjoncteur comporte un mécanisme de commutation destiné à commuter le disjoncteur entre un état ouvert et un état fermé,
• le déclencheur comporte :
  • un actionneur, comprenant un organe de couplage déplaçable entre une position de repos et une position déclenchée, l'organe de couplage étant couplé mécaniquement au mécanisme de commutation pour entraîner la commutation du disjoncteur depuis l'état fermé vers l'état ouvert lorsqu'il passe de la position de repos vers la position déclenchée, et
  • un dispositif de commande, configuré pour alimenter l'actionneur en réponse à la réception, par le déclencheur, d'un signal de commande de déclenchement, pour déplacer l'organe de couplage de la position de repos vers la position déclenchée ;

le déclencheur étant selon la revendication 1 ; Selon encore un autre aspect, l'invention concerne un procédé selon la revendication 9.In another aspect, the invention relates to an electrical apparatus comprising a circuit breaker and a controllable trigger associated with the circuit breaker,

• the circuit breaker comprises a switching mechanism for switching the circuit breaker between an open state and a closed state,
• the trigger includes:
  • an actuator, comprising a coupling member movable between a rest position and a triggered position, the coupling member being mechanically coupled to the switching mechanism to cause circuit breaker switching from the closed state to the open state when moves from the rest position to the triggered position, and
  • a controller configured to supply the actuator in response to the trigger being received by a trigger control signal to move the coupling member from the home position to the triggered position;

the trigger being according to claim 1; According to yet another aspect, the invention relates to a method according to claim 9.

• la figure 1 est une représentation schématique simplifiée d'un appareil électrique comportant un déclencheur commandable conforme à l'invention associé à un disjoncteur électrique :
• la figure 2 représente schématiquement un ordre de déclenchement et d'interruption d'un interrupteur commandable par un module d'excitation d'un dispositif de commande du déclencheur de la figure 1 ;
• la figure 3 représente schématiquement l'évolution, au cours du temps, du courant électrique qui circule au travers d'une bobine d'un actionneur de l'appareil électrique de la figure 1, en réponse aux ordres de déclenchement et d'interruption de la figure 2 ;
• la figure 4 représente schématiquement un module de déclenchement analogique appartenant au dispositif de commande du déclencheur de la figure 1 ;
• la figure 5 représente l'évolution, au cours du temps, de tensions électriques au sein du module de la figure 4 au cours de son fonctionnement ;
• la figure 6 est un ordinogramme d'un procédé de fonctionnement du déclencheur de la figure 1.

The invention will be better understood and other advantages thereof will appear more clearly in the light of the description which follows, of an embodiment of a controllable trigger, given solely by way of example and made in reference to the accompanying drawings in which:

• the figure 1 is a simplified schematic representation of an electrical apparatus comprising a controllable trigger according to the invention associated with an electric circuit breaker:
• the figure 2 schematically represents an order of triggering and interrupting a switch controllable by an excitation module of a control device of the trigger of the figure 1 ;
• the figure 3 schematically represents the evolution, over time, of the electric current flowing through a coil of an actuator of the electrical apparatus of the figure 1 , in response to the trigger and interrupt commands of the figure 2 ;
• the figure 4 schematically represents an analog trigger module belonging to the control device of the trigger of the figure 1 ;
• the figure 5 represents the evolution, over time, of electrical voltages within the module of the figure 4 during its operation;
• the figure 6 is a flowchart of a method of operation of the trigger of the figure 1 .

The figure 1 represents a block diagram of an electrical apparatus 1 comprising an electric circuit breaker 10 and a controllable trigger 20, here coupled to the circuit breaker 10 to control this circuit breaker 10.

The circuit breaker 10 is an electrical circuit breaker, for example a low-voltage and high-current circuit breaker. For example, the voltage is of the order of 690V.

The circuit breaker 10 comprises input and output terminals, which are selectively electrically connected to each other or isolated from each other by separable electrical contacts. The circuit breaker 10 comprises a switching mechanism 110 configured to move these separable electrical contacts between an open state and a closed state. The switching mechanism 110 is here a rocking mechanism, known as the "tumbler" in the English language.

In the open state, the circuit breaker 10 inhibits the flow of electric current between the input and output terminals. In the closed state, the circuit breaker allows the circulation of electric currents between the input and output terminals. The term "opening" is the passage of the circuit breaker 10 from the closed state to the open state.

The circuit breaker 10 further comprises a control lever, or crank pin, coupled to the switching mechanism 110 to allow a user to manually switch the circuit breaker between the open and closed states.

The circuit breaker 10 also comprises a detection circuit configured to switch the mechanism 110 to the open state in the event of detection of an electrical anomaly, such as an overcurrent or a short circuit.

The trip unit 20 is configured to force the circuit breaker 10 to switch from its closed state to its open state when the trip unit receives a trip control signal.

The trigger 20 thus makes it possible to force the switching of the circuit breaker 10 to the open state independently of the detection circuit of the circuit breaker 10. For example, this trip control signal is generated following the action of a user on a switch or an emergency stop type push button which controls a power supply unit which generates the control signal.

In this example, the control signal is an electrical voltage, denoted Vcmd. For example, the control signal Vcmd is a DC voltage. Alternatively, it may be an alternating voltage.

As long as the control signal Vcmd is supplied to the trigger 20, the latter must keep the circuit breaker 10 in the open state. In particular, the trigger 20 should preferentially provide a locking function of the circuit breaker 10 in the open state after having triggered its opening.

Indeed, there is a risk that the moving contacts of the circuit breaker 10 close again if the control lever of the circuit breaker 10 is operated from the position open to the closed position. Such closure is not permitted and therefore must be prevented as it would be contrary to security requirements.

The trigger 20 thus comprises an actuator 210, a control device 220 of the actuator and an input 230 of the control signal Vcmd. Here, the input 230 comprises two terminals, one of which is connected to an electric ground GND of the control device 220.

The actuator 210 is a magnetic actuator, comprising a coil 2101 and a coupling member 2102, adapted to be mechanically coupled to the switching mechanism 110.

The actuator 210 is adapted to be controlled by the control device 220.

The member 2102 is selectively movable between a rest position and a triggered position. The member 2102 is configured so that the movement of its rest position to its triggered position causes the mechanism 110 to switch to open the circuit breaker 10.

In this example, the coupling member 2102 is mechanically coupled to the mechanism 110, for example with the control lever of the circuit breaker 10.

In contrast, in this example, moving the member 2102 from the triggered position to the home position does not automatically cause the mechanism 110 to switch from the open state to the closed state. This switching must here be done manually by acting on the control lever of the circuit breaker 10, for security reasons.

The coil 2101 is configured to move the coupling member 2102 from the rest position to the triggered position when energized with a pulse of an electric current of intensity greater than a first predefined threshold I-min for a period of time. greater than or equal to a predefined duration T-on.

Here, the coupling member 2102 does not automatically return to its rest position as soon as the coil 2101 stops being energized when it is coupled with the control mechanism 110.

In this example, the actuator 210 comprises a magnet, integral with the fixed part of the actuator 210 and a spring, also called trigger spring. The actuator 210 also comprises a movable part, for example mechanically connected to the sensing member 2102. The magnet exerts a magnetic force on the movable part, so that the movable part holds the spring in a compressed state. The restoring force exerted by the spring on the moving part is less than the magnetic force exerted by the magnet. This keeps the coupling member 2102 in the rest position. In other words, the restoring force exerted by the trigger spring is not sufficient to it alone to overcome the magnetic force and move the member 2102 to the triggered position.

The coil 2101 is at least partially adapted to the magnet when it is powered by each of said pulses of electric current applied by the controller 220, so as to reduce the intensity of the magnetic force to a value less than that of the restoring force exerted by the spring, or even to interrupt the magnetic force, and thus allow the movement of the coupling member 2102 from its rest position to the triggered position, under the effect of the restoring force exerted by the trigger spring. In other words, in this example, the coil 2101 is configured to move the coupling member 2102 from the rest position to the indirectly triggered position, in particular via the magnet and the triggering spring. .

For example, the coil 2101 comprises an electrical conductor, such as a copper wire, wound around this magnet to form turns. When the coil 2101 is powered by the electric current pulse, it thus creates a magnetic flux, within the magnet, which opposes the magnetic flux proper to the magnet, thus interrupting the magnetic force.

Thus, in order to move or release the member 2102 to the tripped position, the coil 2101 is supplied with an electrical pulse of intensity greater than the threshold current intensity I-min for the duration at least equal to T-on ( figure 3 ). It is not necessary, unlike known motorized actuators, to maintain a continuous power supply over time. The energy consumption, and therefore the energy dissipation in thermal form, are thus reduced.

The values of the predefined threshold I-min and of the predefined duration T-on are chosen as a function of the actuator 210 and in particular of the quantity of energy that it is necessary to supply to the coil 2101 in order to reduce the magnetic force. at a level below the restoring force of the trigger spring, to cause the displacement of the member 2102 to the triggered position.

In this example, the predefined duration T-on is here equal to 1ms. The minimum intensity I min is such that the magnetic force generated by the coil 2101 is equal to 150 amperes.

In known manner, in the system of units MKS, the magnetic force generated by the coil 2101 is expressed as the product of the intensity of the current which supplies this coil 2101 multiplied by the number of turns of this coil 2101.

For example, the value of the magnetic induction generated by the coil 2101 is sufficient to demagnetize the magnet but not too important to remain lower than the saturation induction of the materials forming the movable and fixed parts of the actuator 210, here equal to 1.5 Tesla.

The controller 220 is configured to power the actuator 210 in response to receiving the control signal Vcmd. The device 220 is also configured to lock the circuit breaker in the open state as long as the control signal Vcmd continues to be applied to the input 230.

More specifically, the control device 220 is configured to electrically power the coil 2101, upon receipt of the control signal Vcmd and as long as the control signal Vcmd is maintained, with a series of pulses of electric current each of duration equal to the predefined duration T-on. The intensity of each of the current pulses of the series is greater than or equal to the first threshold I-min and less than or equal to a second threshold I-max, also called "current limit".

The I-max limit current is greater than the I-min threshold and is less than or equal to 120% of the I-min threshold, preferably less than or equal to 110% of the I-min threshold, more preferably less than or equal to 105% the threshold I-min.

For example, the I-max limit current is equal to 10 mA.

In this example, the coil 2101 comprises a number of turns, denoted N, between 500 and 10000, advantageously chosen as a function of the control voltage Vcmd. The limit current I-max here is equal to I-min x 1.2 / N, or preferably I-min x 1.1 / N, more preferably I-min x 1.05 / N .According to the control voltage Vcmd, the limit current I-max is for example between 15 mA and 265mA.

By choosing the value of the I-max limit current, the power supply of the coil 2101 is optimized according to the characteristics of the actuator 210, so that the coil 2101 is powered with a quantity of energy which is just sufficient to allow the displacement of the coupling member 2102, by demagnetizing the magnet, so as to release the spring but which is not too much greater than what is necessary for this movement. This avoids unnecessary energy consumption and therefore reduces heat dissipation.

In this example, since the control signal Vcmd is an electrical voltage, the control device 220 is adapted to be powered electrically by this control signal Vcmd.

Advantageously, for this purpose, the control device 220 comprises a voltage rectifier 2209 which is connected to the input 230. The rectifier 2209 is here a single-wave rectifier. In this example, it is realized by means of a diode D1 which is placed at the output of the input 230.

In a variant, the rectifier 2209 is a rectifier of the full-wave type. The actuator 210 is then adapted to be used both in a trigger 20 to be controlled by a DC voltage control signal Vcmd or by an AC voltage control signal Vcmd.

Thus, the control device 220 is able to operate, safely, without the need for an on-board power source other than that provided by the control signal Vcmd.

The control device 220 here comprises a current-limited regulated voltage source 2201 and an excitation module 2206. In this example, the excitation module 2206 comprises a programmable microcontroller or a microprocessor.

The source 2201 is here connected in series with the coil 2101 between the input 230 and the GND electrical ground.

The source 2201 is configured to deliver a supply voltage Vcc as soon as it is powered by the control signal Vcmd. In addition, the source 2201 is configured to inject into the coil 2101 an electric current with a maximum amplitude equal to the I-max limit current when it is controlled by the excitation module 2206.

The source 2201 comprises for this purpose a voltage regulator 2202 and a current limiter 2203.

The voltage regulator 2202 is here a linear regulator, comprising a resistor R, a Zener Z diode and a power transistor 2204. The diode Z and the resistor R are connected in series with each other between the output of the rectifier 2209 and the ground GND and a midpoint between the diode Z and the resistor R is connected to a control electrode of the transistor 2204.

The transistor 2204 is here a field effect transistor of MOSFET technology. As a variant, it is replaced by a power transistor of the IGBT type, for "insulated gate bipolar transistor", in particular when the amplitude of the control signal Vcmd is greater. The type of transistor 2204 used depends on the expected maximum amplitude of the control signal Vcmd. In practice, the control signal Vcmd may have a maximum amplitude value of between 12V and 690V.

The voltage regulator 2202 is thus adapted to deliver a supply voltage Vcc on a supply rail Vdd when the control signal Vcmd is applied to the input 230. For example, the voltage Vcc is a DC voltage of amplitude equal to 3.3 volts.

When no control signal Vcmd is applied to the input 230, the voltage regulator 2202 and therefore the source 2201 provide neither voltage nor electric current.

The current limiter 2203 is configured to limit the flow of current therein to the I-max limit value described above. Thus, when the excitation module 2206 allows the injection of a current into the coil 2101, the limiter 2203 prevents the amplitude of this current from exceeding the I-max limit current.

The excitation module 2206 is configured to be electrically powered by the supply voltage Vcc and to control the generation of electric current pulses by means of the source 2201.

More specifically, the excitation module 2206 is programmed to, successively, activate and then inhibit the injection of the electric current by the current-limited regulated voltage source 2201, to generate each pulse of electric current, the activation then the inhibition being separated by a delay greater than or equal to the predefined delay T-on.

The current-limited regulated voltage source 2201 is configured to inject into the coil 2101 an electric current in response to a trip command issued by the excitation module 2206, and, alternately, to interrupt the flow of this current. in response to an interrupt command generated by the excitation module 2206.

In this example, the control device 220 comprises a controllable switch T1 connected in series with the coil 2101 and the source 2201 between the input 230 and the GND electrical ground. A control electrode of the transistor T1 is electrically connected to a control output of the excitation module 2206.

The switch T1 is here a MOSFET transistor.

In this example, the switch T1 is by default in a blocking state, thus preventing the flow of an electric current between the output of the source 2201 and the electrical ground and thus preventing the supply of the coil 2101.

When the module 2206 sends a trip command on the transistor T1, the latter goes into an on state, thereby allowing the flow of electric current through the coil 2101.

When the module 2206 sends an interrupt command to the transistor T1, the latter returns to its blocking state, again preventing the flow of electric current through the coil 2101.

Thus, the module 2206 controls the source 2201 by means of the switch T1.

Advantageously, the voltage regulator 2202 also comprises a stabilization circuit of the supply voltage Vcc. This stabilization circuit is here formed by a diode D2 and a capacitor C, connected in series between the supply rail Vdd and the ground GND in parallel with the switch T1. This stabilization circuit is intended to prevent the supply voltage Vcc collapses during operation of the excitation module 2206 and in particular when the switch T1 goes into the on state.

Advantageously, the control device comprises a measuring probe 2205 of the current flowing through the coil 2101. Then, the excitation module 2206 is programmed to control the inhibition of the power supply by emitting a command. interruption at the expiration of the predetermined time T-on, this time being counted by the excitation module 2206, from the moment when the current measured by the measuring probe 2205 exceeds the threshold value I-min.

The measurement probe 2205 is here a precision resistor connected in series with the coil 2101 and connected to a measurement input of the excitation module 2206.

The figure 2 represents, as a function of time t, the evolution of a control signal of the switch T1 between its on states, denoted "ON" and blocking, denoted "OFF" emitted by the module 2206. Note t0 instant , called "trigger time", from which the module 2206 sends a trip command to switch the switch T1 in the on state.

As illustrated in figure 3 , from this moment t0, the current increases until reaching the limit current I-max, limited by the limiter 2203.

The rate at which the current increases from the instant t0 depends on the position of the coupling member 2102. Depending on whether the member 2102 is in the rest position or in the triggered position, the inductance value of the 2101 coil is not the same. Here, the inductance of the coil 2101 is higher when the member 2102 is in the idle state. In fact, the response of the coil 2101 to the current flowing through it is different.

The curve C1 represents the change in the intensity of the current flowing in the coil 2101 after the instant t0 when the member 2102 is in the tripped position.

We denote "t1" the moment from which this current exceeds the threshold I-min. After this time t1, the current continues to increase until reaching the I-max limit current. The excitation module 2206 counts down the elapsed time, for example by means of a timer, from the instant t1, while keeping the switch T1 in the on state.

When the countdown time exceeds the preset time T-on, the excitation module 2206 sends an interrupt command at a time t3. The switch T1 returns to its blocking state and the current thus ceases to flow in the coil 2101.

The curve C2 represents the change in the intensity of the current flowing in the coil after the instant t0 when the member 2102 is in the rest position.

Due to the inductance difference of the coil 2101, the electric current increases, since time t0, more slowly than for the curve C1.

We denote by "t2" the instant from which the current exceeds the threshold value I _MIN . The difference between the instants t2 and t0 is greater than the difference between the instants t1 and t0.

After this time t2, the current continues to increase until reaching the I-max limit current. As before, the excitation module 2206 holds the switch T1 in the on state and sends an interrupt command at a time t4 at the expiration of the delay T-on. The current then ceases to flow through the coil 2101.

Thus, the excitation module 2206 does not allow the circulation of an electric current longer than necessary to form a pulse of duration T-on, which reduces the electrical consumption of the trigger 20, and thus reduces the heat dissipation.

More precisely, if such a regulation were not applied, then it would be necessary to predefine the closing time of transistor T1 as being equal to the difference of times t4 and t0, based on the worst case scenario, which is that where the self inductance of the coil is minimal, so as to be sure to always have a pulse of duration at least equal to the duration T-one whatever the state of the coil 2101. In this case, the duration of the pulse would have been too long, since the current would have continued to be applied between instants t3 and t4, then the coil 2101 had received enough energy for the displacement of the organ 2102 is ensured. It would therefore have generated excessive heating for nothing, because the current supplied between times t1 and t3 is sufficient to excite the coil and cause switching.

Advantageously, the excitation module 2206 comprises a detection module configured to measure the nature of the control signal Vcmd and in particular to determine whether it is an electrical or alternating voltage. This determination is made here from the voltage of the rail Vdd.

• synchroniser automatiquement la génération des impulsions de courant électrique avec le signal de commande Vcmd, lorsque le signal de commande Vcmd est détecté comme étant une tension électrique continue ou alternative, c'est-à-dire lorsque la tension du rail Vdd est détectée comme étant alternative redressée à mono alternance ou double alternance, cette synchronisation étant réalisée en générant les ordres de déclenchement aux instants où le signal de commande Vcmd prend une valeur nulle, et, alternativement,
• commander la génération des impulsions de courant électrique avec une période prédéfinie, si le signal de commande Vcmd est détecté comme étant une tension électrique continue.

The excitation module 2206 is further programmed to detect the nature of the control signal with the aid of this detection module and to adapt the time transmission of the tripping commands, and in particular for:

• automatically synchronize the generation of the pulses of electric current with the control signal Vcmd, when the control signal Vcmd is detected as being a DC or AC voltage, that is to say when the voltage of the rail Vdd is detected as alternating rectified with mono alternation or double alternation, this synchronization being achieved by generating the trigger commands at times when the control signal Vcmd takes a null value, and, alternatively,
• controlling the generation of electrical current pulses with a predefined period, if the control signal Vcmd is detected as a DC voltage.

Synchronization with the control signal Vcmd makes it possible to generate the pulses of electric current when the latter has a minimum value, and thus to limit the electrical power consumed by the control device 220.

Preferably, the excitation module 2206 is programmed so that the delay between two consecutive pulses is less than or equal to 100 ms, preferably less than or equal to 50 ms.

This delay, or interval, is noted T-off and is defined as the time interval between two current pulses at an intensity value greater than or equal to the I-min threshold. In this example, the T-off delay is 40ms.

et $\frac{1}{100},$

de préférence égal à $\frac{1}{40},$

ce qui permet de réduire la puissance consommée.The duty cycle between the T-on delay and the T-off delay, defined as the T-on / T-off ratio between the T-on and T-off delays, is advantageously between $\frac{1}{10}$

and $\frac{1}{100},$

preferably equal to $\frac{1}{40},$

which reduces the power consumed.

This delay is chosen so as to limit the risk of failure to open the circuit breaker 10. In a known manner, the switching mechanisms 110 of the toggle type comprise an open limit position, denoted P1, and a dead position closing, noted P2. These points P1 and P2 correspond to intermediate positions of the switching mechanism between the open state and the closed state.

The point P1 corresponds to the position of the mechanism 110 from which the opening of the circuit breaker is guaranteed. In other words, when the mechanism 110 passes the point P1 from the closed position, the opening of the circuit breaker 10 is guaranteed. The point P1 corresponds to the release position of an element of the trigger mechanism 110 known as the trigger half-moon.

Alternatively, the circuit breaker 10, the point P1 coincides with the opening position of the circuit breaker.

The point P2 corresponds to the position of the mechanism 110 from which the closure of the circuit breaker can no longer be prevented. In other words, when the mechanism 110 crosses the point P2 coming from the open position, the closure of the circuit breaker 10 is provided. This is due to the action of mechanical springs included within the switching mechanism 110.

Thus, this choice of value of the T-off delay makes it possible to guarantee that at least one pulse is generated from the module 2206 when the switching mechanism 110 is between the points P1 and P2 during its movement between the closed and open states. . With this pulse, the coupling member 2102 is again moved to its tripped position and again forces the opening of the circuit breaker before the switching mechanism 110 crosses the point P2.

Advantageously, the control device 220 also comprises an analog excitation module 2208 configured to generate, in addition, a single pulse of electric current of intensity greater than or equal to the first predetermined threshold I-min, as soon as the signal is received. Vcmd command by the controller 220.

This analog excitation module 2208 is distinct from the excitation module 2206. Similarly, the single current pulse generated using this module 2208 is distinct from the series of pulses generated by means of the excitation module. 2206.

As illustrated in figure 4 , the module 2208 comprises a comparator 2210 and a monostable flip-flop 2211. The control device 220 comprises meanwhile a controllable switch T2, for example identical to the switch T1.

The switch T2 is here connected in parallel with the switch T1 between the source 2201 and the ground GND. The switch T2 plays, vis-à-vis the source 2201, a role similar to that described for the switch T1 with reference to the module 2206.

The comparator 2210 is configured to compare the supply voltage value Vcc with a predefined reference value Vref.

As illustrated in figure 5 when the supply voltage Vcc is applied and exceeds the reference value Vref, the comparator 2210 delivers a voltage, here denoted V1, to an input of the monostable flip-flop 2211.

For example, the value Vref is equal to 3 volts.

Monostable flip-flop 2211 is configured to output a single output voltage pulse, which pulse has a predefined duration T '. This output is connected to a control electrode of the transistor T2 and acts as a switching command of the switch T2.

The monostable flip-flop 2211 is chosen so as to have a duration T 'long enough to guarantee that the pulse of electric current generated has a duration greater than the duration T-on. As an illustrative example, the duration T 'is here equal to 18 ms.

Alternatively, the switch T2 can be omitted. In this case, the module 2208 is adapted to control the switch T1 in parallel with the module 2206, for example by means of an "AND" logic gate which collects the commands issued by the modules 2206 and 2208 and which consequently controls the switch T1.

The module 2208 is used in addition to the module 2206 and makes it possible to ensure that at least one pulse of electric current is injected into the coil 2201 as soon as the control signal Vcmd is received on the input 230, even in case of failure. of the module 2206. This single pulse has a duration and intensity sufficient to ensure the movement of the member 2102 to its tripped position.

Indeed, since the module 2208 is made from simple analog components, and not from programmable microcontrollers or microprocessors, it has a more reliable and robust operation than the module 2206. This ensures a good operational safety of the module. trigger 20.

Although the module 2208 does not allow to optimize the duration of the single pulse as finely as the module 2206 allows, this is not detrimental since only one current pulse is generated. by means of the module 2208 each time the control signal Vcmd is initiated. The additional energy cost is thus minimal.

In the example illustrated, the trip unit 20 has an average consumption, in steady state, of less than or equal to 1 W and a transient consumption during power-up, that is to say the reception of the signal. Vcmd control, is less than or equal to 10 W. By comparison, in the known actuator actuators, the average steady-state consumption is greater than 5 W and transient consumption is greater than 30 W. Thanks to the In the invention, the heat dissipation is considerably reduced.

An example of operation of the electrical apparatus 1 and the trigger 20 is now described with reference to the flowchart of the figure 6 and with the help of Figures 1 to 5 .

Initially, during a step 1000, the circuit breaker 10 is in a closed state, allowing the passage of an electric power current between its input and output terminals. No control signal Vcmd is received on the input 230. The coupling member 2102 is held in the home position. No electric current is injected into the coil 2101.

Then, in a step 1002, the control signal Vcmd is applied to the input 230 to the trigger 20, for example in response to the action of a user who press an emergency stop button to request opening of the circuit breaker 10.

This voltage Vcmd feeds the rectifier 2209 and therefore the source 2201. Since the transistors T1 and T2 are both in the open state, no current flows at that moment through the coil 2101. The source 2201 therefore does not charge any electric current at that time. However, the voltage regulator 2202 generates the voltage Vcc on the power rail, which in turn powers the excitation modules 2206 and 2208.

During a step 1004, the excitation module 2208 controls the generation, by the source 2201, of a single current pulse to the coil 2101.

For example, as soon as the excitation module 2208 is powered by the supply voltage Vcc greater than the reference value Vref, the comparator 2210 delivers the voltage V1 to the input of the monostable flip-flop 2211.

In response, the monostable flip-flop 2211 goes into an excited state during the duration T ', during which it outputs a non-zero voltage V2 and then returns to a state of rest at the end of this period T'. In doing so, the monostable flip-flop 2211 sends an opening switching and then closing order of the switch T2, separated by this delay T '.

Accordingly, in a step 1006, the coil 2101 demagnetizes the magnet and allows the spring to move to its relaxed position, which allows the displacement of the coupling member 2102 from its rest state to the triggered state . The coupling member 2102 acts on the switching mechanism 110 which causes the circuit breaker 10 to open.

In parallel with step 1004, the excitation module 2206 is powered by the supply voltage Vcc in order to generate the series of current pulses.

Thus, in a step 1008, the excitation module 2206 automatically detects whether the control signal Vcmd is a DC voltage or an AC voltage.

If the control signal Vcmd is determined to be a DC voltage, then, in a step 1010, the current pulses are generated periodically over time, here with a delay equal to the T-off delay. Advantageously, for each pulse, from the tripping moment t0 of the switch T1, the excitation module 2206 detects, by virtue of the current probe 2205, the instant from which the current flowing in the coil 2101 becomes greater than or equal to the threshold voltage I-min and then sends an interrupt command of the switch T1 on expiration of the delay T-on after this instant.

If, on the contrary, the control signal Vcmd is determined as being an alternating voltage, then, during a step 1012, the current pulses are generated. synchronously with the instants for which the control signal Vcmd is detected as taking a zero value. More precisely, it is the tripping times t0 for which the excitation module 2206 sends a tripping order of the switch T1 which are synchronized with the times for which the control signal Vcmd is detected as taking a zero value. The generation of each of the pulses from this triggering instant t0 is here the same as that described for step 1010.

The pulses generated by means of the excitation module 2206 make it possible to bring and / or maintain the circuit breaker 10 in the open state. In the step 1006, as long as the control signal Vcmd is applied to the input 230, the excitation module 2206 continues to generate the pulses so that the coil 2101 continues to demagnetize the magnet so as to allow the spring of remain in its relaxed position and thus maintain the coupling member 2102 in its triggered state.

Finally, in a step 1014, the control signal Vcmd ceases to be applied and is no longer received on the input 230. The source 2201 is interrupted and the supply voltage Vcc becomes zero. The excitation module 2206 then stops working, and no electric current pulse is sent into the coil 2101.

An operator can then manually reset the circuit breaker 10 to bring it back into the closed state, by means of the control lever. The process described can then be repeated.

The embodiments and alternatives contemplated above may be combined with one another to generate new embodiments, still within the scope of the appended claims.

Claims (9)

1. Controllable release switch (20) for an electrical circuit breaker (10), the circuit breaker being switchable between an open state and a closed state, this release switch comprising:

   - an actuator (210) comprising a coupling element (2102) which is displaceable between an inoperative position and a released position, the coupling element (2102) being intended to be coupled mechanically to a switching mechanism (110) of an electrical circuit breaker (10) in order to cause the switching of the circuit breaker (10) from a closed state towards an open state when the coupling element (2102) passes from the inoperative position towards the released position, and

   - a control device (220), configured in order to supply the actuator, in response to receipt, by the release switch (20), of a release control signal (Vcmd), in order to displace the coupling element (2102) from the inoperative position towards the released position;

   the actuator (210) being a magnetic actuator comprising a coil (2101), configured in order to displace the coupling element (2102) from the inoperative position towards the released position when it is supplied with an electrical current pulse of intensity greater than a first predefined threshold (I-min) for a duration greater than or equal to a predefined duration (T-on), the release switch (20) being characterised
   in that the control device (220) is configured in order to supply electrically the coil (2101), upon receipt of the control signal (Vcmd) and as long as the control signal (Vcmd) is maintained, with a series of electrical current pulses of duration equal to the predefined duration (T-on) and of intensity greater than or equal to the first threshold (I-min) and less than or equal to a second threshold (I-max), this second threshold (I-max) being at most equal to 120% of the first threshold (I-min);
   in that the control signal (Vcmd) is an electrical voltage, received at an input (230) of the release switch (20), the control device (220) being adapted in order to be supplied electrically by the control signal (Vcmd), in that the control device (220) comprises:

   - a regulated, current-limited voltage source (2201), connected in series with the coil (2101) between the input (230) and an electrical earth (GND) of the control device (220), this regulated, current-limited voltage source (2201) being configured in order to deliver a supply voltage (Vcc) on a supply rail as long as it is supplied by the control signal (Vcmd),

   - an excitation module (2206), configured in order to be supplied electrically by the supply voltage (Vcc) and in order to control the generation of the electric current pulses,

   the regulated, current-limited voltage source (2201) being, furthermore, configured in order to inject selectively into the coil (2101) an electrical current of intensity equal to the second predetermined threshold (I-max) and, alternately, to interrupt the circulation of this electrical current, in response to release and interruption orders generated by the excitation module (2206);
   in that the control device (220) comprises a probe (2205) for measuring the current which circulates through the coil (2101), and in that the excitation module (2206) is programmed in order, successively, to activate then inhibit the injection of the electrical current by the regulated, current-limited voltage source (2201), in order to generate each electrical current pulse, the excitation module (2206) being programmed in order to control this inhibition at the end of the predetermined delay (T-on), this delay being counted by the excitation module (2206) from the moment when the current measured by the measuring probe (2205) exceeds the first threshold value (I-min).
2. Release switch according to claim 1, characterised in that the control device (220) comprises a controllable interrupter (T1), connected in series with the coil (2101) and the regulated, current-limited voltage source (2201) between the input (230) and the electrical earth (GND), the control of the source being produced by the excitation module (2206) by means of this interrupter (T1), the interrupter (T1) being for this purpose connected to the excitation module (2206) and being able to switch between a passing state and a blocking state in order, respectively, to allow or inhibit the circulation of the electrical current, in response to the release and interruption orders, respectively, generated by the excitation module (2206).
3. Release switch according to any of the claims 1 to 2, characterised in that the excitation module (2206) is programmed in order to detect if the control signal (Vcmd) is a continuous or alternating electrical voltage, and in order to:

   - synchronise automatically generation of the electrical current pulses with the control signal (Vcmd) if the control signal (Vcmd) is detected as being an alternating electrical voltage, this synchronisation being produced by the excitation module (2206) by generating the release orders at the moments when the control signal (Vcmd) assumes a zero value, and, alternatively,

   - control the generation of the electrical current pulses with a predefined period if the control signal (Vcmd) is detected as being a continuous electrical voltage.
4. Release switch according to any of the claims 1 to 3, characterised in that the excitation module (2206) is programmed in order to control the generation of the electrical current pulses with a predefined interval (T-off) between two consecutive electrical current pulses, the predefined interval (T-off) being less than or equal to 100 ms.
5. Release switch according to claim 4, characterised in that the cyclic ratio between the predetermined delay (T-on) and the predefined interval (T-off) is between $\frac{1}{10}$

   

   and $\frac{1}{100},$

   

   preferably equal to $\frac{1}{40}.$

   
6. Release switch according to any of the preceding claims, characterised in that the control device (220) comprises an analogue excitation module (2208), configured in order to generate, furthermore, a single electrical current pulse, of intensity greater than or equal to the first predetermined threshold (I-min), upon receipt of the control signal (Vcmd) by the control device (220).
7. Release switch according to any of the preceding claims, characterised in that the actuator (210) comprises furthermore a magnet, a mobile part connected mechanically to the coupling element (2102) and a release spring, the magnet being integral with a fixed part of the actuator (210) and exerting a magnetic force on the mobile part when the coupling element (2102) is in the inoperative position, such that the mobile part compresses the spring in order to maintain the coupling element (2102) in the inoperative position, the spring exerting a restoring force in opposition to the magnetic force, and having an intensity less than the magnetic force, the coil (2101) being adapted in order to reduce the magnetic attraction force exerted by the magnet when it is supplied by each of said electrical current pulses applied by the control device (220), so as to allow movement of the coupling element (2102) from its inoperative position towards the released position, under the effect of the restoring force exerted by the release spring.
8. Electrical assembly (1) comprising a circuit breaker (10) and a release switch (20) which is controllable and connected to the circuit breaker,

   - the circuit breaker (10) comprising a switching mechanism (110) intended to switch the circuit breaker between an open state and a closed state,

   - the release switch (20) comprising:

   - an actuator (210), comprising a coupling element (2102) which is displaceable between an inoperative position and a released position, the coupling element (2102) being coupled mechanically to the switching mechanism (110) in order to cause switching of the circuit breaker (10) from the closed state towards the open state when it passes from the inoperative position towards the released position, and

   - a control device (220), configured in order to supply the actuator in response to receipt, by the release switch (20), of a release control signal (Vcmd), in order to displace the coupling element (2102) from the inoperative position towards the released position;

   the release switch (20) being characterised in that it is according to any of the preceding claims.
9. Method for controlling a release switch (20) for an electrical circuit breaker (10), this method being characterised in that it comprises the steps:

   a) of providing a release switch, comprising

   - an actuator (210), comprising a coupling element (2102) which is displaceable between an inoperative position and a released position, the coupling element (2102) being intended to be coupled mechanically to a switching mechanism (110) of an electrical circuit breaker (10) in order to cause switching of the circuit breaker (10) from a closed state towards an open state when the coupling element (2102) passes from the inoperative position towards the released position, the actuator (210) being a magnetic actuator comprising a coil (2101), configured in order to displace the coupling element (2102) from the inoperative position towards the released position when it is supplied with an electrical current pulse of intensity greater than a first predefined threshold (I-min) for a duration greater than or equal to a predefined duration (T-on), and

   - a control device (220), configured in order to supply the actuator, in response to receipt, by the release switch (20), of a release control signal (Vcmd), in order to displace the coupling element (2102) from the inoperative position towards the released position, the control device (220) comprising:

   - a source of regulated, current-limited voltage (2201), connected in series with the coil (2101) between the input (230) and an electrical earth (GND) of the control device (220), this source of regulated, current-limited voltage (2201) being configured in order to deliver a supply voltage (Vcc) on a supply rail as long as it is supplied by the control signal (Vcmd),

   - an excitation module (2206), configured in order to be supplied electrically by the supply voltage (Vcc) and in order to control the generation of the electrical current pulses, the control device (220) comprising furthermore a probe (2205) for measuring the current which circulates through the coil (2101);

   b) of acquiring a release control signal (Vcmd) by the release switch (20), the control signal (Vcmd) being an electrical voltage, received on an input (230) of the release switch (20), the control device (220) being adapted in order to be supplied electrically by the control signal (Vcmd);

   c) of supplying the coil (2101) by the control device (220) with a series of electrical current pulses of duration equal to the predefined duration (T-on) and of intensity greater than or equal to the first threshold (I-min) and less than or equal to a second threshold (I-max), this second threshold (I-max) being at most equal to 120% of the first threshold (I-min), this supply being applied upon receipt of the control signal (Vcmd) and as long as the control signal (Vcmd) continues to be received by the release switch (20), the regulated, current-limited voltage source (2201) injecting into the coil (2101) an electrical current of intensity equal to the predetermined second threshold (I-max) and, alternately, interrupting the circulation of this electrical current, in response to the release and interruption orders generated by the excitation module (2206), the excitation module (2206) activating then inhibiting the injection of the electrical current by the regulated, current-limited voltage source (2201), by controlling this inhibition at the end of the predetermined delay (T-on), this delay being counted by the excitation module (2206), from the moment when the current measured by the measuring probe (2205) exceeds the first threshold value (I-min).

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