AU633426B2

AU633426B2 - Testing device for earth leakage circuit breakers

Info

Publication number: AU633426B2
Application number: AU76115/91A
Authority: AU
Inventors: Johannes Becker; Uwe Bock
Original assignee: Felten and Guilleaume Energietechnik AG
Current assignee: Felten and Guilleaume AG
Priority date: 1990-04-11
Filing date: 1991-04-29
Publication date: 1993-01-28
Anticipated expiration: 2011-04-29
Also published as: CN1056372A; DE9004196U1; ATE112093T1; ES2060220T3; DE4011680A1; EP0451481B1; CN1021167C; EP0451481A2; DE59102992D1; JPH04230930A; AU7611591A; EP0451481A3

Abstract

2.1 Test devices for earth-fault circuit breakers have the object of closing an auxiliary circuit when a test button is operated, in order to be able to test the operation of the earth-fault circuit breaker. In this case, it must be ensured that the auxiliary circuit cannot be closed in the switched-off state. 2.2 The invention indicates a means by which a test device is combined with an auxiliary circuit and a test button (7) having a contact position display device (6), a switch shaft (1) which is connected to the moving contact (2) additionally being equipped with a bending spring (4) which is used not only as an operating device for the contact position display device (6) but also makes contact with a contact spring (5) of the auxiliary circuit when the contacts (2, 3) are closed. When the contacts (2, 3) are opened, the contact spring (5) cannot make contact with the bending spring (4), so that the auxiliary circuit remains opened even if the test button (7) is operated. 2.3 The test device can be used in all types of earth-fault circuit breakers, but is particularly suitable for earth-fault circuit breakers of narrow construction. <IMAGE>

Description

COMMONWEALTH OF AUSTRAL 4 PATENTS ACT 1952 Form COMPLETE SPECIFICATION

ORIGINAL

FOR OFFICE USE Short Title: Int Cl: Application Number: Lodged: Complete Specification-Lodged: Accepted: Lapsed: Published: Priority: Related Art: t TO BE COMPLETED BY APPLICANT Name of Applicant: FELTEN GUILLEAUME ENERGIETECHNIK

AKTIENGESELLSCHAFT

1 Address of Applicant: Schanzenstrasse 24-30, D-5000 KOLN 80, GERMANY Actual Inventor: Johannes Becker and Uwe Bock Address for Service: GRIFFITH HACK CO 71 YORK STREET SYDNEY NSW 2000 Complete Specification for the invention entitled: TESTING DEVICE FOR EARTH LEAKAGE C.RCUIT BREAKERS The following statement is a full description of this invention, including the best method of performing it known to us:- GH&CO REF: 21507-D:CLC:RK S5346A:rk 1 f I o 0 0 0 0 ooo 0 000000 0o o o 0 00 0000 0 0 0 0 0 0 c 0 0 0 00 0 0 0 0 0 9 2 Felten Guilleaume Energietochnik AG, D-5000 Koln Description: Testing device for earth leakage circuit breakers.

The invention concerns a testing device for earth leakage circuit breakers in a4cordancz with the-- Praml-e.f- 4 GC-a-im-3-.

This type of testing device, which is kewf from DE- PS 26 18 295, is required for testing the functional reliability and readiness of fault current tripping devices used in earth leakage circuit breakers. This testing function is performed by depressing the test key which, in by-passing the summation transformer, closes a current circuit, namely the auxiliary circuit, via a test resistor between two phases. This simulates a fault current which causes the tripping device of the earth leakage circuit breaker to respond and release the mechanism of the earth leakage circuit breaker.

An earth leakage circuit breaker, which is provided with a test key for the purpose of closing a test circuit, thereby simulating a fault current which causes the tripping device of the earth leakage S l oSe d (n circuit breaker to respond, is known fre DE-PS 27 33 837. With this known type of testing device, the mating contact of the switch for the testing circuit is formed by a part of the swi.tch mechanism which, when the latter is tripped, swings out of reach of one of the legs of a leg spring.

In the case of the aforementioned earth leakage circuit breakers it is not possible to recognize with any certainty the actual position of the main contacts. The position of the switch lever gives only an approximate indication of their position.

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fl flc~urW -3- The invention is based on the technical problem of developing, for earth leakage circuit breakers of the above mentioned type, a testing device which can be combined with a contact position indicating device in a small space and using common parts which are designed to perform both testing and contact position indicating functions.

The advantages achieved with the preferred embodiment of the invention consist in the fact that the number of parts required for the functions "auxiliary circuit" and "contact position indication" can be reduced, thus permitting their use in earth leakage circuit breakers of smaller construction.

According to the present invention there is provided a testing device for an earth leakage circuit breaker having a stationary and movable contact, an actuating shaft for moving the movable contact, a cantilever spring having one end connected to the actuating shaft, a contact position indicating device having a pivot and a lever which is arranged to contact the other end of the cantilever spring, the testing device comprising a test button and an auxiliary circuit having a contact spring and with two extended ends where at one end the contact spring is pivotable on an axis, wherein in use the test button is actuable to move the pivotable end of the contact spring 25 from a first to a second position, the pivotable end of the contact spring being arranged to contact the cantilever L spring when the contacts are closed and being arranged not to contact the cantilever spring when the contacts are i A" i open.

A preferred embodiment of the present invention will now be described by way of example only with reference to "t.4 the accompanying drawings.

Fig. 1 A testing device combined with a contact position indicating device in an earth leakage circuit 35 breaker shown in side elevation and in cross- S"section, position: ON, test key: OFF Fig. 2 A part of this combination shown in front elevation and in cross-section, in the same position as shown in Fig. 1 S :21507D/438/11 .11. 92 I Fig.3 This same combination in position: OFF, test key: OFF Fig.4 This same combination in position: ON, test key: ON This same combination in position: OFF, test key: ON.

In the earth leakage circuit breaker depicted in Figs. 1 to 5, an actuating shaft 1 with a moving contact 2 and a stationary contact 3 are positioned in the bottom part of the circuit breaker housing 11ii.

A cantilever spring 4, which projects into the top part of the circuit breaker housing 11, is connected to the actuating shaft 1. The end of the cantilever spring 4 corresponds with a lever 61 belonging to the contact position indicating device 6 which is provided with a pivot 10. The freedom of movement of the cantilever spring 4 is limited by two stops 63 and 64 located on the lever 61. The contact position indicating device 6 is equipped, opposite lever 61, cr with a further lever 62 which is divided into two equal sections, each one identified by different colours. Only one of these sections of the lever 62 is visible through an aperture 12 in the circuit o breaker housing 11 at any one time. The position of the moving contact 2 is transmitted to the contact position indicating device 6 via the actuating shaft 1 and the cantilever spring 4 and made visible from the outside by the corresponding coloured section of the lever 62 which appears in the opening 12 of the circuit breaker housing 11. The rotational movement of the lever 62 is limited by the stops 8 and 9.

The testing device consists of a test key 7 with an extension pin 71 which is of such a length that it can make contact with a contact spring 5. The contact spring 5 takes the form of a torsion spring with a pivot 52 and has a bend 51 at its centre.

r- II The mode of operation of the testing device is as follows: When test key 7 is actuated, the testing device closes an auxiliary circuit by means of which the operation of the earth leakage circuit breaker can be tested. It sieu4 not be possible to close the auxiliary circuit when the earth leakage circuit breaker is switched off.

When the earth leakage circuit breaker is in the "ON" position and the test key is in the "OFF" position, as shown in Figs. 1 and 2, the cantilever spring 4, which is conductively connected to the moving contact 2 and firmly attached in the actuating shaft 1, turns the contact position indicating device 6 around the pivot 10 in a counterclockwise direction towards the stop 9. The moving contact 2 is moved by the actuating shaft 1 in the direction of the stationary contact 3. The corresponding identification colour of the contact position indicating device 6 is now visible through the aperture 12 of the circuit breaker housing 11.

0o° When both the earth leakage circuit breaker and the test key are in the "OFF" position, as shown in Fig.

3, the cantilever spring 4 turns the contact position indicating device 6 in a clockwise direction towards o the stop'8. The corresponding identification colour of the contact position indicating device 6 is now visible through the aperture 12 of the circuit breaker housing 11.

When both the earth leakage circuit breaker and the test key are in the "ON" position, as shown in Fig.

4, the auxiliary circuit closes upon actuation of the test key 7, whereby the contact spring 5 touches the cantilever spring 4.

When the earth leakage circuit breaker is in the "OFF" position U the test key is in the "ON" position, the noving contact 2 is open. In this case the auxiliary circuit cannot be closed, even if the test key 7 is actuated.

Claims

1. A testing device for an earth leakage circuit breaker having a stationary and movable contact, an actuating shaft for moving the movable contact, a cantilever spring having one end connected to the actuating shaft, a contact position indicating device having a pivot and a lever which is arranged to contact the other end of the cantilever spring, the testing device comprising a test button and an auxiliary circuit having a contact spring and with two extended ends where at one end the contact spring is pivotable on an axis, wherein in use the test button is actuable to move the pivotable end of the contact spring from a first to a second position, the pivotable end of the contact spring being arranged to contact the cantilever spring when the contacts are closed and being arranged not to contact the cantilever spring when the contacts are open.

2. A testing device according to claim 1, characterised in that the contact position indicating device is provided with a segmental lever which is divided into two sections identifiable by different colours.

3. A testing device according to one of claims 1 and 2, characterised in that the lever of the contact position indicating device on the side facing the cantilever spring is provided with two stops, between which the other end of the cantilever spring is movable.

4. A testing device according to any one of claims 2 and 3, characterised in that the movement of the 30 segmental lever of the contact position indicating device is limited by two stops which are spaced at such a distance that only one of the identifying colours of the segmental lever is visible through an aperture in the housing of the earth leakage circuit breaker. 35

5. A testing device according to any one the claims 1 to 4, characterised in that the contact spring takes the form of a helical coil, the one end of the contact spring is in the form of a free end which is S:21507D/438/11.11.92 J a a *t I t. a a i ti t ;i a 1 r^j o o l *a K t (r t' 4I :I-1 rr ii r -p 7 bent, and in that an extension pin belonging to the test button engages the contact spring at its bend, and wherein the other end of the contact spring is clamped.

6. A testing device for earth leakage circuit breakers substantially as hereinbefore described with reference to the accompanying drawings. Dated this 11th day of November 1992 FELTEN GUILLEAUME ENERGIETECHNIK AKTIENGESELLSCHAFT By their Patent Attorneys GRIFFITH HACK CO 0 4 I 0 a4 00 o. 0 a 4 0 0 I 0 S:21507D/438/11.11.92