EP0264313B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Electric differential-protection apparatus with a test circuit
Assignee: Merlin Gerin SA
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Filing: 1987-09-16
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Granted: 1992-01-29
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Expires: 2007-09-16
Abstract
Abstract The test circuit (28) of a differential circuit-breaker comprises a leakage branch circuit having two test resistors (34, 36), a test button (44), and a protection device with two isolating contacts (40, 42). Following differential triggering, the opening of the two contacts (40, 42) ensures that the test button (44) and the remotely-controlled contact (46) are taken out of circuit independently of the mode of supply upstream or downstream of the circuit-breaker. <IMAGE>
Inventors
- 👤 René Challande
- 👤 Patrick De Robertis
- 👤 Jacky Duchenaud
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 20:45
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/26; H02H3/32; H02H3/33; H02H3/334; H02H3/335; H01; H01H; H01H83/00; H01H83/02; H01H83/04; H01H2083/045
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
234 words
An electrical differential protection unit, notably a circuit breaker (10) or switch, having a multipole breaking device (12) with separable contacts (14, 16) actuated by an operating mechanism (18), and a differential trip device (20) comprising a residual differential current detector with a summing transformer (21), a trip relay (26) supplied by said detector so as to transmit a tripping order to the mechanism (18) when a differential current occurs, and a test circuit (28) having at least one test resistance in a branched leakage circuit connected between two connecting points (30, 32) of the active conductors (L, N) of the power supply system, respectively upstream and downstream from the transformer (21), the test circuit (28) comprising a test button (44) closing of which creates an artificial differential current detected by said detector, and a protective device (38) capable of disconnecting said resistance and of interrupting the artificial differential current in the test circuit (28) after opening of the multipole breaking device (12) by differential tripping of the unit, characterized in that the protective device (38) of the test circuit (28) comprises a pair of interrupting contacts (40, 42) arranged between the connecting points (30, 32) of the active conductors (L, N) and the test button (44) so as to ensure that the power supply to the test button (44) is cut after differential tripping regardless of the connection mode of the electrical unit.
Claim 2
Dependent Claim
42 words
The electrical differential protection unit according to claim 1, characterized in that the test circuit (28) comprises two test resistances (34, 36) connected respectively between the connecting points (32, 30) of the active conductors (L, N) and the interrupting contacts (42, 40).
Claim 3
Dependent Claim
54 words
The electrical differential protection unit according to claim 2, characterized in that the test button (44) is electrically connected in series with the two interrupting contacts (42, 40), opposite from the test resistances (34, 36), each terminal (50, 52) of the test button (44) being connected directly to the corresponding interrupting contact (42, 40).
Claim 4
Dependent Claim
92 words
The electrical differential protection unit according to claim 3, comprising a remote tripping control cooperating with the differential trip device (20) to bring about remote-controlled opening of the multipole breaking device (12) by artificial differential tripping, characterized in that the remote tripping control comprises a remote control means (46) connected in a link circuit (48) capable of being electrically connected in parallel to the terminals (50, 52) of the test button (44), the assembly being arranged to isolate the test button (44) and remote control means (46) when the unit is open.
Claim 5
Dependent Claim
191 words
The electrical differential protection unit according to one of the claims 1 to 4, the differential trip device (20) comprising in addition a first mechanical link (27) capable of transmitting the tripping order from the relay (26) to the operating mechanism (18), and a second mechanical link (45) with the operating mechanism (18) with handle to derive an automatic reset movement of the relay (26) from the opening movement of the multipole breaking device (12), the second mechanical link (45) being equipped with a reset lever (76) pivotally mounted on a spindle (80) between a first and a second stable position corresponding to opening and closing of the unit, characterized in that the reset lever (76) cooperates simultaneously with the two interrupting contacts (40, 42) of the test circuit (28) to bring about automatic opening of said contacts (40, 42) when the relay (26) is reset corresponding to movement of the reset lever (76) to the first position, and reclosing of said contacts (40, 42) when the reset lever (76) is moved to the second position in the course of closing of the operating mechanism (18) with handle of the unit.
Claim 6
Dependent Claim
71 words
The electrical differential protection unit according to claim 5, characterized in that the reset lever (76) cooperates on the one hand with a cam (70) transmitting the movement of the handle of the operating mechanism (18), and on the other hand with a drive lever (64) for transmission of the resetting movement of the relay (26), said lever (64) also bearing a finger (68) forming the first mechanical tripping link (27).
Claim 7
Dependent Claim
110 words
The electrical differential protection unit according to claim 5 or 6, characterized in that one of the interrupting contacts (40) of the test circuit (28) comprises a torsion spring (92) made of conducting material threaded onto the pivoting spindle (80) of the reset lever (76), and comprising an end strand capable of coming into engagement with a first stationary conducting strip (96) when closing of the interrupting contact (40) takes place corresponding to the second position of the reset lever (76), the spring (92) being arranged to bias the reset lever (76) to the first position enabling the relay (26) to be reset, and the interrupting contact (40) to open.
Claim 8
Dependent Claim
70 words
The electrical differential protection unit according to claim 6 or 7, characterized in that the other interrupting contact (42) of the test circuit (28) comprises a flexible contact blade (102) actuated by a finger (103) of the reset lever (76), and able to cooperate in the closed position of the contact (42) with a second stationary conducting strip (100) when the reset lever (76) is moved to the second position.
References Cited (Backward Citations)
No citation records indexed.
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