Racking interlocking systems for withdrawable circuit breakers

Patent metadata

Field	Value
Publication number	US-9843174-B2
Application number	US-201615065014-A
Country	US
Kind code	B2
Filing date	Mar 9, 2016
Priority date	Mar 9, 2016
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

An interlocking system for a circuit breaker assembly including a circuit breaker having a plurality of contacts includes a racking screw coupled to the contacts that changes a position of the circuit breaker when engaged by a tool. The interlocking system also includes a front panel defining an opening through which the racking screw is accessible, an access door coupled to the front panel and configured to selectively cover the opening, and an access door stopper coupled to the front panel. The interlocking system also includes a trip assembly coupled to the access door stopper. Each of the access door, the access door stopper, and the trip assembly are moveable between a first position and a second position such that moving to the first position triggers delivery of a trip signal to the circuit breakers to open the plurality of contacts, and wherein, in the second position, the access door is fully open to enable access to the racking screw through the front panel.

First claim

What is claimed is:

1. A method of assembling a draw-out breaker assembly including a circuit breaker having a plurality of contacts, said method comprising:
coupling an interlock system to a front panel of a base assembly, wherein coupling the interlock system comprises:
coupling an access door to the front panel such that the access door selectively covers an opening formed in the front panel;
coupling an access door stopper to the front panel and to the access door, wherein the access door stopper is selectively moveable between a first trip position and a first open position; and
coupling a racking screw to the front panel and to the plurality of contacts;

coupling a trip assembly to the front panel and to the access door stopper, wherein the trip assembly is selectively moveable between a second trip position and a second open position, such that:
i) when the access door stopper is in the first trip position,
ii) when the trip assembly is moved to the second trip position by the access door stopper to engage a trip bar of the circuit breaker, and
iii) when the access door is partially opened such that access to the racking screw through the opening is prevented, a trip signal is provided to the circuit breaker to position the plurality of contacts in a third open position, and

such that:
i) when the access door stopper is moved to the first open position,
ii) when the trip assembly is moved to the second open position by the access door stopper, and
iii) when the access door is fully opened by the trip assembly to enable access to the racking screw, a position of the plurality of contacts is confirmed.

2. The method in accordance with claim 1 , wherein the coupling the trip assembly comprises coupling the trip assembly such that when the trip bar is rotated, using the trip assembly, the trip signal is provided to the circuit breaker to trip the circuit breaker.

3. The method in accordance with claim 1 , wherein the coupling the trip assembly comprises:
coupling a trip link of the trip assembly to the access door stopper;
coupling an actuation slider to the trip link; and
coupling an actuation cam system to the actuation slider.

4. The method in accordance with claim 1 , wherein the coupling the trip assembly comprises:
coupling a trip bar extension to the trip bar such that moving the trip assembly to the second trip position causes rotation of the trip bar extension and the trip bar; and
coupling an actuator to the trip bar extension and to a circuit breaker mechanism such that the rotation of the trip bar causes linear movement of the actuator to trip the circuit breaker mechanism.

5. The method in accordance with claim 1 , wherein the coupling the access door stopper to the front panel comprises coupling the access door stopper to the front panel such that a portion of the access door stopper extends through the front panel.

6. The method in accordance with claim 1 , further comprising coupling a contacts position indicator to the circuit breaker such that when the trip assembly is moved to the second open position, the trip assembly advances passed the contacts position indicator in the circuit breaker to enable the access door to fully open.

7. The method in accordance with claim 1 , further comprising removably coupling a tool, by inserting the tool through the opening in the front panel, to the racking screw such that rotation of the tool causes rotation of the racking screw to rack the circuit breaker.

8. The method in accordance with claim 1 , wherein the coupling the interlocking system further comprises coupling a lock link to the front panel such that the lock link is moveable between a first locked position and a first unlocked position.

9. The method in accordance with claim 8 , wherein the coupling the interlocking system further comprises coupling a lever link to the lock link such that the lever link is moveable between a second locked position and a second unlocked position, wherein, when the lock link is in the first locked position and the lever link is in the second locked position, opening of the access door is prevented.

10. The method in accordance with claim 9 , further comprising:
coupling a key lock to the front panel; and
coupling a key lock latch to the key lock and to the lock link such that rotation of the key lock and key lock latch prevents movement of the lock link.

11. An interlocking system for a draw-out circuit breaker assembly including a circuit breaker having a plurality of contacts, said interlocking system comprising:
a racking screw coupled to the plurality of contacts that changes a position of the circuit breaker within the draw-out circuit breaker assembly when engaged by a tool;
a front panel defining an opening through which said racking screw is selectively accessible;
an access door coupled to said front panel and configured selectively cover the opening to selectively provide access to said racking screw;
an access door stopper coupled to and at least partially extending through said front panel, said access door stopper configured to limit movement of said access door based on a position of the plurality of contacts; and
a trip assembly coupled to said access door stopper, wherein said access door is moveable between a first trip position and a first open position, said access door stopper is moveable between a second trip position and a second open position, and said trip assembly is moveable between a third trip position and a third open position, wherein moving said access door to the first trip position, said access door stopper to the second trip position, and said trip assembly to the third trip position triggers delivery of a trip signal to the circuit breaker to open the plurality of contacts, and wherein, in the first open position the access door is fully open to enable access to said racking screw through said front panel.

12. The interlocking system in accordance with claim 11 , wherein said access door stopper in the second trip position and said trip assembly in the third trip position provide the trip signal to the circuit breaker to open the plurality of contacts, and wherein said access door stopper is fully open to enable access to said racking screw through said front panel in the first open position to verify an open position of the plurality of contacts.

13. The interlocking system in accordance with claim 12 , wherein said trip assembly comprises a trip link coupled to said access door stopper, an actuation slider coupled to said trip link, and an actuation cam system coupled to said actuation slider, wherein said actuation cam system engages a trip bar of the circuit breaker to provide the trip signal.

14. The interlocking system in accordance with claim 11 , wherein, in the first trip position, said access door prevents access to said racking screw and, in the first open position, said access door allows access to said racking screw.

15. The interlocking system in accordance with claim 11 , further comprising a contacts position indicator moveable between a fourth open position and a failure position corresponding to the position of the plurality of contacts, wherein said contacts position indicator, in the fourth open position, enables movement of said trip assembly to the third open position and wherein said contacts position indicator, in the failure position, prevents movement of said trip assembly to the third open position.

16. The interlocking system in accordance with claim 11 , wherein movement of said access door stopper to the second trip position causes movement of said trip asse

Assignees

• Gen Electric

Inventors

• Cieply Przemyslaw Eugeniusz
• Rzepecki Ryszard
• Candelora Andrew Matthew
• Tumu Nagesh V
• Wasik Szymon
• Davis Alisha M

Classifications

• H01H11/00

  Apparatus or processes specially adapted for the manufacture of electric switches (processes specially adapted for manufacture of rectilinearly movable switches having a plurality of operating members associated with different sets of contacts, e.g. keyboards, H01H13/88) · CPC title

• H02B11/133 Primary

  with interlock · CPC title

• H02B1/06

  having associated enclosures, e.g. for preventing access to live parts · CPC title

• H01H9/26

  for interlocking two or more switches ({H01H13/568 takes precedence;} by a detachable member H01H9/28 {; for electromagnetic relays H01H50/323}) · CPC title