FR2694458A1 - Detecting position of electromagnetic relay contacts - using device with circuit including photocouplers, resistors and capacitors connected to supplying source of relay coil and generating signals applied to alarm and control circuit - Google Patents
Detecting position of electromagnetic relay contacts - using device with circuit including photocouplers, resistors and capacitors connected to supplying source of relay coil and generating signals applied to alarm and control circuit Download PDFInfo
- Publication number
- FR2694458A1 FR2694458A1 FR9209620A FR9209620A FR2694458A1 FR 2694458 A1 FR2694458 A1 FR 2694458A1 FR 9209620 A FR9209620 A FR 9209620A FR 9209620 A FR9209620 A FR 9209620A FR 2694458 A1 FR2694458 A1 FR 2694458A1
- Authority
- FR
- France
- Prior art keywords
- coil
- photodiode
- photocoupler
- contacts
- lines
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H47/00—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
- H01H47/002—Monitoring or fail-safe circuits
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3277—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches
- G01R31/3278—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches of relays, solenoids or reed switches
Abstract
Description
DISPOSITIF DE DETECTION DE LA COHERENCE ENTRE L'ETAT DES
CONTACTS D'UN RELAIS ET L'ETAT D'EXCITATION DE SA BOBINE
La présente invention est relative aux installations électriques comportant des relais électromécaniques commandant des organes de manoeuvre, de commande ou de signalisation. L'invention s'applique en particulier aux installations électriques protégées au moyen d'appareils de protection tels que des disjoncteurs, commandés par des relais électromécaniques.DEVICE FOR DETECTING THE CONSISTENCY BETWEEN THE STATE OF
CONTACTS OF A RELAY AND THE EXCITATION OF ITS COIL
The present invention relates to electrical installations comprising electromechanical relays controlling operating, control or signaling members. The invention applies in particular to electrical installations protected by means of protective devices such as circuit breakers, controlled by electromechanical relays.
Le mauvais fonctionnement d'un relais peut entraîner de graves conséquences pour l'installation électrique. Un mauvais fonctionnement d'un relais peut résulter de plusieurs situations décrites ci-après:
- des contacts d'un même relais peuvent rester "collés", que la bobine soit excitée ou non, alors que l'état de la bobine devait entraîner la séparation de ces contacts,
- des contacts d'un même relais, formant un inverseur, ne ferment aucun circuit dans un état stable du relais,
- des contacts d'un même relais, lors des états stables de celui-ci, devraient être dans le même état de conduction et ne le sont pas.The malfunction of a relay can have serious consequences for the electrical installation. A malfunction of a relay can result from several situations described below:
- Contacts of the same relay can remain "bonded", whether the coil is energized or not, while the state of the coil should cause the separation of these contacts,
- contacts of the same relay, forming an inverter, do not close any circuit in a stable state of the relay,
- contacts of the same relay, during stable states thereof, should be in the same conduction state and are not.
Certains relais, dits de sécurité, éliminent le dernier des mauvais fonctionnements précités, mais pas les deux premiers. Certain relays, called safety relays, eliminate the last of the aforementioned malfunctions, but not the first two.
Un but de la présente invention est de définir un dispositif simple permettant de détecter toute incohérence entre les états des contacts d'un relais et celui de sa bobine de commande. An object of the present invention is to define a simple device making it possible to detect any inconsistency between the states of the contacts of a relay and that of its control coil.
L'invention a pour objet un dispositif de détection de la cohérence entre l'état des contacts d'un relais électromagnétique et l'état d'excitation de la bobine alimentée par une source de tension à travers un interrupteur, ledit relais comprenant n contacts mobiles pouvant prendre, selon l'état alimenté ou non de la bobine une première position dans laquelle ils polarisent n premières lignes alimentées par n sources de potentiel et une seconde position dans laquelles ils polarisent n secondes lignes à la terre, n étant un nombre entier, caractérisé en ce qu'il comprend un premier photocoupleur comprenant une photodiode en parallèle sur la bobine en aval de l'interrupteur et un phototransistor connecté entre l'anode de ladite photodiode et ladite source, le collecteur du phototransistor dudit premier photocoupleur étant relié à la photodiode d'un photocoupleur de sortie comportant un phototransistor constituant les sorties du dispositif reliées à un circuit d'alarme et/ou de commande, le dispositif comprenant en outre, une première série de n photocoupleurs dont les phototransistors sont reliés en série entre le collecteur de la photodiode du premier photocoupleur et la photodiode du photocoupleur de sortie, et dont les photodiodes correspondantes sont reliées respectivement entre les premières lignes et des sources de potentiel opposées à celles des premières lignes, et une seconde série de n photocoupleurs dont les phototransistors sont connectés en série entre le point commun à la bobine et à l'interrupteur et la photodiode du photocoupleur de sortie, et dont les photodiodes correspondantes sont reliées respectivement entre les secondes lignes et des sources de potentiel opposées à celles des premières lignes. The subject of the invention is a device for detecting the consistency between the state of the contacts of an electromagnetic relay and the state of excitation of the coil supplied by a voltage source through a switch, said relay comprising n contacts. mobiles which can take, depending on the energized or not state of the coil, a first position in which they polarize n first lines supplied by n potential sources and a second position in which they polarize n second lines to earth, n being an integer , characterized in that it comprises a first photocoupler comprising a photodiode in parallel on the coil downstream of the switch and a phototransistor connected between the anode of said photodiode and said source, the collector of the phototransistor of said first photocoupler being connected to the photodiode of an output photocoupler comprising a phototransistor constituting the outputs of the device connected to a power circuit weapon and / or control device, the device further comprising a first series of n photocouplers, the phototransistors of which are connected in series between the collector of the photodiode of the first photocoupler and the photodiode of the output photocoupler, and of which the corresponding photodiodes are connected respectively between the first lines and potential sources opposite to those of the first lines, and a second series of n photocouplers whose phototransistors are connected in series between the point common to the coil and to the switch and the photodiode of the output photocoupler , and whose corresponding photodiodes are connected respectively between the second lines and potential sources opposite to those of the first lines.
L'invention sera bien comprise à la lecture de la description d'un exemple de réalisation, en référence au dessin annexé dans lequel:
- la figure unique est un schéma électrique représentant un relais électromécanique muni du dispositif de détection de cohérence de l'invention.The invention will be clearly understood on reading the description of an exemplary embodiment, with reference to the appended drawing in which:
- The single figure is an electrical diagram representing an electromechanical relay provided with the coherence detection device of the invention.
Dans la figure, la référence 1 désigne la bobine d'un relais alimentée par une source de tension continue -C +C à travers un interrupteur 2; la bobine est protégée par une diode D. In the figure, reference 1 designates the coil of a relay supplied by a DC voltage source -C + C through a switch 2; the coil is protected by a diode D.
Dans l'exemple choisi, la bobine commande le mouvement simultané de deux contacts 3 et 4 qui, selon leur position, ferment des lignes R1, R2 ou T1, T2. Les lignes sont alimentées par des potentiels +P1 et +P2 respectivement définis par rapport à des potentiels -P1 et -P2. In the example chosen, the coil controls the simultaneous movement of two contacts 3 and 4 which, depending on their position, close lines R1, R2 or T1, T2. The lines are supplied by potentials + P1 and + P2 respectively defined with respect to potentials -P1 and -P2.
Le dispositif de détection de cohérence comporte tout d'abord une branche qui fournit un signal représentatif de l'état alimenté ou de l'état non alimenté de la bobine 1. The coherence detection device firstly comprises a branch which supplies a signal representative of the energized state or the unpowered state of the coil 1.
Cette branche comprend un photocoupleur PC1 comprenant une photodiode D1 et un phototransistor TC1. L'anode de la photodiode D1 du photocoupleur TC1 est reliée, par une résistance R1, à la liaison d'alimentation de la bobine 1, en un point Q situé entre la bobine et l'interrupteur 2, sa cathode étant reliée au potentiel -C; le phototransistor TC1 est connecté entre les bornes -C et +C, par l'intermédiaire d'une résistance R2.This branch comprises a photocoupler PC1 comprising a photodiode D1 and a phototransistor TC1. The anode of the photodiode D1 of the photocoupler TC1 is connected, by a resistor R1, to the supply link of the coil 1, at a point Q located between the coil and the switch 2, its cathode being connected to the potential - VS; the phototransistor TC1 is connected between the terminals -C and + C, via a resistor R2.
Le schéma de l'invention comporte plusieurs autres photocoupleurs; pour la clarté du schéma les photodiodes et les phototransistors de ces photocoupleurs ont été représentés éloignés les uns des autres. The diagram of the invention includes several other photocouplers; for the sake of clarity of the diagram, the photodiodes and phototransistors of these photocouplers have been shown distant from each other.
Au point Q est reliée une branche comprenant, en série, une résistance R3, les phototransistors TC2 et TC4 de deux photocoupleurs PC2 et PC4, une résistance R4 et la photodiode D6 d'un photocoupleur de sortie PC6; la photodiode D6 est reliée au potentiel -C; les sorties S1 et S2 du phototransistor TC6 du photocoupleur PC6 constituent les sorties de l'appareil de contrôle et sont reliées à un circuit d'alarme ou de commande non représenté. Un condensateur C1 est connecté en parallèle aux bornes de la photodiode D6. At point Q is connected a branch comprising, in series, a resistor R3, the phototransistors TC2 and TC4 of two photocouplers PC2 and PC4, a resistor R4 and the photodiode D6 of an output photocoupler PC6; photodiode D6 is connected to potential -C; the outputs S1 and S2 of the phototransistor TC6 of the photocoupler PC6 constitute the outputs of the control device and are connected to an alarm or control circuit not shown. A capacitor C1 is connected in parallel to the terminals of the photodiode D6.
Entre le collecteur du phototransistor PC1 et l'émetteur du phototransistor TC4 sont disposés en série les phototransistors TC3 et TC5 de deux photocoupleurs PC3 et
PC5.Between the phototransistor collector PC1 and the phototransistor transmitter TC4 are arranged in series the phototransistors TC3 and TC5 of two photocouplers PC3 and
PC5.
La photodiode D2 du photocoupleur PC2 est reliée, en série avec une résistance R5, entre la ligne T2, en aval du contact 4, et le potentiel -P2; de même, la photodiode D3 du photocoupleur PC3 est reliée, en série avec une résistance
R6, entre la ligne R2, en aval du contact 4, et le potentiel -P2.The photodiode D2 of the photocoupler PC2 is connected, in series with a resistor R5, between the line T2, downstream of the contact 4, and the potential -P2; similarly, the photodiode D3 of the photocoupler PC3 is connected, in series with a resistor
R6, between line R2, downstream of contact 4, and potential -P2.
La photodiode D4 du photocoupleur PC4 est reliée, en série avec une résistance R7, entre la ligne T1, en aval du contact 3, et le potentiel -P1; de même, la photodiode D5 du photocoupleur PC5 est reliée, en série avec une résistance
R8, entre la ligne R1, en aval du contact 3-, et le potentiel -P1. The photodiode D4 of the photocoupler PC4 is connected, in series with a resistor R7, between the line T1, downstream of the contact 3, and the potential -P1; similarly, the photodiode D5 of the photocoupler PC5 is connected, in series with a resistor
R8, between line R1, downstream of contact 3-, and potential -P1.
Le fonctionnement du dispositif est décrit maintenant. The operation of the device is now described.
On suppose qu'en fonctionnement normal, lorsque la bobine est alimentée, les contacts 3 et 4 appliquent le potentiel P1 sur la ligne T1 et le potentiel P2 sur la ligne
T2, et que, lorsque la bobine cesse d'être alimentée, les contacts 3 et 4 retombent et appliquent le potentiel P1 sur la ligne R1 et le potentiel P2 sur la lignre R2.It is assumed that in normal operation, when the coil is energized, contacts 3 and 4 apply the potential P1 on the line T1 and the potential P2 on the line
T2, and that, when the coil ceases to be supplied, the contacts 3 and 4 fall back and apply the potential P1 on the line R1 and the potential P2 on the line R2.
Dans le dessin, le contact 2 est fermé, la bobine 1 est alimentée et les contacts 3 et 4 polarisent les lignes T1 et T2. La photodiode D1 est alimentée de sorte que le transistor TC1 conduit; les photodiodes D2 et D4 sont alimentées de sorte que les phototransistors TC2 et TC4 conduisent; la photodiode D6 conduit et le phototransistor fournit par suite un signal de sortie sur les bornes S1 et
S2, ce signal étant interprété comme un signe du bon fonctionnement du relais.In the drawing, the contact 2 is closed, the coil 1 is supplied and the contacts 3 and 4 polarize the lines T1 and T2. The photodiode D1 is supplied so that the transistor TC1 conducts; photodiodes D2 and D4 are supplied so that phototransistors TC2 and TC4 conduct; the photodiode D6 conducts and the phototransistor consequently supplies an output signal on the terminals S1 and
S2, this signal being interpreted as a sign of the correct functioning of the relay.
Supposons que la bobine cesse d'être alimentée (ouverture de l'interrupteur 2) et que les contact 3 et 4 restent collés, continuant à fermer les lignes T1 et T2. Suppose that the coil stops being supplied (opening of the switch 2) and that the contacts 3 and 4 remain glued, continuing to close the lines T1 and T2.
Les phototransistors TC2 et TC4 des photocoupleurs PC2 et PC4 restent passants puisque les photodiodes D2 et D4 sont alimentées, mais aucun signal n'est transmis au photocoupleur PC6 puisque le phototransistor TC1 du photocoupleur PC1 est bloqué (photodiode D1 non alimentée) et que les phototransistors TC3 et TC5 sont bloqués, les photodiodes D3 et D5 n'étant pas alimentées. L'absence de signal aux bornes S1S2 est interprété comme un signe de défaillance et entraîne le déclenchement d'une alarme ou la mise en route d'un circuit de secours. The phototransistors TC2 and TC4 of the photocouplers PC2 and PC4 remain conductive since the photodiodes D2 and D4 are supplied, but no signal is transmitted to the photocoupler PC6 since the phototransistor TC1 of the photocoupler PC1 is blocked (photodiode D1 not supplied) and that the phototransistors TC3 and TC5 are blocked, the photodiodes D3 and D5 are not supplied. The absence of a signal at terminals S1S2 is interpreted as a sign of failure and leads to the triggering of an alarm or the activation of an emergency circuit.
Supposons que les contacts 3 et 4, après un changement d'état de la bobine 1, restent en position intermédiaire sans fermer ni les lignes R1R2 ni les lignes TlT2. Suppose that the contacts 3 and 4, after a change of state of the coil 1, remain in the intermediate position without closing neither the lines R1R2 nor the lines TlT2.
ler cas: la bobine B est alimentée. 1st case: coil B is energized.
le phototransistor TC1 conduit mais les phototransistors TC3 et TC5 restent bloqués, les diodes D3 et D5 n'étant plus alimentées. Pour la même raison, les phototransistors TC2 et TC4 restent bloqués. Aucun signal n'est transmis à la photodiode D6 de sorte qu'il n'y a plus de signal aux bornes de S1S2. the phototransistor TC1 conducts but the phototransistors TC3 and TC5 remain blocked, the diodes D3 and D5 being no longer supplied. For the same reason, phototransistors TC2 and TC4 remain blocked. No signal is transmitted to the photodiode D6 so that there is no longer any signal at the terminals of S1S2.
2ème cas: la bobine n'est pas alimentée. 2nd case: the coil is not supplied.
Il est clair qu'aucune alimentation de la photodiode
D6 n'est possible, de sorte qu'aucun signal n'apparaît aux bornes de S1S2.It is clear that no supply of the photodiode
D6 is not possible, so that no signal appears at the terminals of S1S2.
Supposons que la bobine soit alimentée, que le contact 3 polarise normalement la ligne T1, mais que le contact 4 ne polarise ni R2 ni T2. Aucun signal n'est transmis à la photodiode D6 puisque les phototransistors TC3 et TC4 restent bloqués. Suppose that the coil is supplied, that contact 3 normally polarizes line T1, but that contact 4 does not polarize R2 or T2. No signal is transmitted to photodiode D6 since phototransistors TC3 and TC4 remain blocked.
Supposons enfin que la bobine soit alimentée, que le contact 3 polarise normalement la ligne T1, mais que le contact 4 polarise la ligne R2. Aucun signal n'est transmis à la photodiode D6 puisque les phototransistors TC2 et TC5 restent bloqués. Suppose finally that the coil is supplied, that contact 3 normally polarizes line T1, but that contact 4 polarizes line R2. No signal is transmitted to photodiode D6 since phototransistors TC2 and TC5 remain blocked.
On voit que tous les défauts possibles sont détectés par le dispositif; on note que le dispositif de l'invention effectue en grande partie sa propre autosurveillance, puisque toute défaillance des phototransistors PC1 et PC6 sera immédiatement décelée. We see that all possible faults are detected by the device; it is noted that the device of the invention largely performs its own self-monitoring, since any failure of the phototransistors PC1 and PC6 will be immediately detected.
Une diode électroluminescente de signalisation LED peut être placée en série avec la photodiode D6 du photocoupleur PC6. An LED light-emitting diode can be placed in series with the photodiode D6 of the photocoupler PC6.
L'invention s'applique bien entendu à un relais qui comporterait un seul contact mobile ou plus de deux contacts mobiles, en retranchant ou en ajoutant les photocoupleurs correspondant aux lignes fermées par ces contacts. The invention obviously applies to a relay which would comprise a single movable contact or more than two movable contacts, by subtracting or adding the photocouplers corresponding to the lines closed by these contacts.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR9209620A FR2694458B1 (en) | 1992-08-03 | 1992-08-03 | Device for detecting the consistency between the state of the contacts of a relay and the state of excitation of its coil. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR9209620A FR2694458B1 (en) | 1992-08-03 | 1992-08-03 | Device for detecting the consistency between the state of the contacts of a relay and the state of excitation of its coil. |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| FR2694458A1 true FR2694458A1 (en) | 1994-02-04 |
| FR2694458B1 FR2694458B1 (en) | 1994-09-16 |
Family
ID=9432571
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR9209620A Expired - Fee Related FR2694458B1 (en) | 1992-08-03 | 1992-08-03 | Device for detecting the consistency between the state of the contacts of a relay and the state of excitation of its coil. |
Country Status (1)
| Country | Link |
|---|---|
| FR (1) | FR2694458B1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109324284A (en) * | 2017-07-31 | 2019-02-12 | 比亚迪股份有限公司 | The sintering detection method and its sintering detection system of relay in discharge loop |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56101203A (en) * | 1980-01-14 | 1981-08-13 | Yamatake Honeywell Co Ltd | Control device |
| JPS57189073A (en) * | 1981-05-18 | 1982-11-20 | Nissan Motor Co Ltd | Checker for relay |
| BE898572A (en) * | 1983-12-28 | 1984-04-16 | Dumont Pierre Yves | Relay circuit with safety cut=out - has two interconnected relays in series reducing risk of contacts remaining closed after removal of excitation current |
| US4977478A (en) * | 1989-04-07 | 1990-12-11 | Alcatel Na, Inc., | Contact status detector |
-
1992
- 1992-08-03 FR FR9209620A patent/FR2694458B1/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56101203A (en) * | 1980-01-14 | 1981-08-13 | Yamatake Honeywell Co Ltd | Control device |
| JPS57189073A (en) * | 1981-05-18 | 1982-11-20 | Nissan Motor Co Ltd | Checker for relay |
| BE898572A (en) * | 1983-12-28 | 1984-04-16 | Dumont Pierre Yves | Relay circuit with safety cut=out - has two interconnected relays in series reducing risk of contacts remaining closed after removal of excitation current |
| US4977478A (en) * | 1989-04-07 | 1990-12-11 | Alcatel Na, Inc., | Contact status detector |
Non-Patent Citations (2)
| Title |
|---|
| PATENT ABSTRACTS OF JAPAN vol. 5, no. 173 (P-87)5 Novembre 1981 & JP-A-56 101 203 ( YAMATAKE HONEYWELL ) 13 Août 1981 * |
| PATENT ABSTRACTS OF JAPAN vol. 7, no. 35 (P-175)(1180) 10 Février 1983 & JP-A-57 189 073 ( NISSAN ) * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109324284A (en) * | 2017-07-31 | 2019-02-12 | 比亚迪股份有限公司 | The sintering detection method and its sintering detection system of relay in discharge loop |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2694458B1 (en) | 1994-09-16 |
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