GB2299453A

GB2299453A - Circuit breaker

Info

Publication number: GB2299453A
Application number: GB9506343A
Authority: GB
Inventors: Roger Neil Castonguay; Jeffrey A Lord
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1995-03-28
Filing date: 1995-03-28
Publication date: 1996-10-02
Anticipated expiration: 2015-03-28
Also published as: GB2299453B; GB9506343D0

Abstract

A circuit breaker trip indication device comprises a switch actuator 16 which is movable against the bias of a return spring 21 in response to operation of a trip unit to actuate a microswitch 19 to provide a remote indication of the operation of the trip unit. A button 12 of the microswitch 19 is in abutment with the switch actuator 16 when the switch actuator 16 is in its rest position.

Description

Cur Circuit breakers as described in U.S. Patent 3,073,936 are used to protect equipment and humans from damage or harm due to overcurrent in an electrical power distribution system. For the purpose of remotely identifying the breaker position within its compartment, position switch devices are used. On occasions there is a requirement to know the position of the circuit breaker contacts to determine if the breaker is open or closed. This can be accomplished by the use of an auxiliary switch device. In other cases where these breakers are used as main or tie breakers in a double or triple ended substation with a power management system, there is a need to identify the position of the breaker in its compartment and its contact position. Breakers which have electronic trip units as described in U.S. patent 4,672,501 work in concert with a tripping device.

These tripping devices, after receiving a signal from the electronics to trip the breaker.

must be mechanically reset. A typical reset arrangement is described in U.S. patent 4,301,435.

Zg'RtPD V LE.) .N VENTIQN A contact position switch 11 as seen in Fig 1 is mounted to the associated breaker (not shown) by means of a mounting plate 18. A microswitch 19 is mounted to plate 18 by means of bolts 20 and 25, lock washer 23 and nuts 22. The switch actuator 16 is mounted to plate 18 by means of bolt 20 and nut 22 and is supported by rollers 17 to actuate switch button 12. Switch actuator 16 is held against switch button 12 by spring 21 which is anchored between switch actuator holes 13 and 14 at one end and bolt 20 at the other end.

Switch actuator tail 15 engages stationary bracket 24 mounted in the breaker compartment. The interaction between tail 15 and bracket 24 activates and deactivates switch 19 in a manner determined by the position of the circuit breaker in its respective compartment.

The contact position switch 11 shown in Figure 2 interacts with and is mounted within a tripping device 9 similar to that described in British Provisional Application Serial No.

P88296. The contact position switch 11 is mounted to a mounting plate 18(a) by bolts 20 and 25 and lock nuts 22. The mounting plate 18(a) is attached to the inside of frame 26 and held in place by bolt 27 and lock washer 28. The switch button 12 is actuated by tab 30 which extends from switch actuator link 16(a) and which pivots about pivot 29 incorporated in the above mentioned tripping device. Tab 30 is rotated into engagement with switch button 12 by spring 21(a) and is rotated away from switch button 12 indirectly by the action of the circuit breaker contacts (not shown).

Application P88296 referenced above is at annex A to this application.

The tripping device 9A shown in Fig 3 operates an electric trip unit in the manner described in the aforementioned British Provisional Application Serial No. P88296. The trip unit is attached to Lc mounting plate 18(b). Reset lever 33 is fastened to the mounting plate 18(b) by spacer 34 and bolt 35. Extension link 36 is attached to reset lever 33 at pivot 37 and is attached to reset bellcrank 38 at pivot 39. Reset bellcrank 38 is rotatably attached to pivot 40 which is incorporated within trip unit. The interaction of the aforementioned components with the circuit breaker operating components automatically resets the electric trip unit.

The tripping device shown 9B in Fig 4 includes an electric trip unit which is described in aforementioned British Provisional Application Serial No. P88296. The tripping device is mounted to a mounting plate 18(c). Reset lever 33(a) is pivotably mounted to plate 18(c) at pivot 44. Extension link 36(a) is attached to reset lever 33(a) at pivot 37(a) and is attached to reset bellcrank 38(a) at pivot 39(a). Reset bellcrank 38(a) is rotatably attached to pivot 40(a) which is incorporated within tripping device 9B. The interaction of the tripping device components with the associated circuit breaker resets the electric trip unit.

The tripping device 9C shown in Fig 5 also includes an electric trip unit which is described in aforementioned British Provisional Application Serial No. P88296 The tripping device is mounted to mounting plate 18(d). Reset lever 33(b) is pivotably mounted to reset bellcrank 38(b) at pivot 39(b). Reset lever 33(b) is also guided by slot 48 in mounting plate 18(d). Reset bellcrank 38(b) is rotatably attached to pivot 40(b) which is incorporated within tripping device 9C. The interaction of the tripping device components with the associated circuit breaker resets the electric trip unit.

The tripping device 9D shown in Fig 6 further includes an electric trip unit which is described in aforementioned British Provisional Application Serial No. P88296. The tripping device is mounted to mounting plate 18(e). Mounting plate 18(e) is assembled to mounting bracket 52. Reset lever 33(c) is pivotably mounted to reset bellcrank 38(c) at pivot 39(c). Reset bellcrank 38(c) is rotatably attached to pivot 40(c) which is incorporated within tripping device 9D. The interaction of the tripping unit components with the associated circuit breaker resets the electric trip unit.

In a double or triple ended substation which incorporates a power management system. as shown in figure 7, the auxiliary panels must receive breaker contacts position logic for efficient operation. By utilizing a plurality of the contact position switch assemblies. I 1 of Figures 1 and 2, in the two main breakers, 62 and 64, and the tie circuit breaker 63 this logic can be easily achieved. The contact position switch and assemblies are adaptable to different breakers designs for allowing existing substations to become converted to a power management system.

Claims

1. A circuit breaker trip indication device comprising: a switch actuator (16) arranged proximate a circuit breaker trip unit (9); a microswitch (19) proximate said switch actuator and arranged for interracting with said switch actuator to provided remote indication of operation of said circuit breaker trip unit; an actuator tail (15) at one end of said switch actuator arranged for contacting a part of said trip unit upon occurance of a trip operation; a return spring (21) connecting with said switch actuator for returning said switch actuator to a home position after said trip unit is reset.

2. The trip indication device of claim I including a reset cable connected with said switch actuator for returning said switch actuator to said home position.

3. The trip indication device of claim 1 wherein said microswitch includes a button (12) in abutment with said switch actuator when said switch actuator is in said home position.

4. A trip indication device comprising: a circuit breaker trip bar support; a circuit breaker trip bar (9) pivotally-attached to said support for tripping a circuit breaker upon occurance of an overcurrent condition; a switch actuator link (16A) connecting with said trip bar; an actuator tab (30) pivotally-attached to said trip bar support and arranged for rotating in response to operation of said trip bar; a microswitch (11) attached to said trip bar support; a button (12) extending from said microswitch and arranged for contact with said actuator tab when said trip bar rotates, said button thereby opening or closing said switch to provide remote indication of said overcurrent occurance.

5. The trip indication device of claim 4 inlcuding a reset bellcrank (38A) connecting with said circuit breaker trip bar.

6. The trip indication device of claim 5 further including a reset lever (33A) connecting with said bellcrank through an extension link (36A) for resetting said trip bar after said overcurrent condition has abated. The trip indication device of claim

7. A circuit breaker indication device as claimed in claim 1 substantially as described by way of example with reference to any one of Figures 1 to 6.

8. A trip indication device as claimed in claim 4 substantially as described by way of example with reference to any one of Figures 1 to 6.