The remote indication of a circuit breaker status

Abstract

 A circuit breaker and a status monitor assembly which includes a circuit breaker housing having a circuit breaker mechanism therein and a status monitor fastened to the circuit breaker housing. The status monitor has an actuating member located within the circuit breaker housing, a switch operable by the actuating member, and a set of output terminals connected to the switch. The actuating member is displaceable by a component of the circuit breaker mechanism. The invention also provides a circuit breaker status monitor usable with a circuit breaker having a housing with a circuit breaker mechanism therein, to monitor its status. Further, the invention also provides a circuit breaker which has an aperture into which an actuating member of an associated status monitor may be inserted.

Description

[0001] THIS INVENTION relates to circuit breakers. More particularly, the invention relates to the indication of the status of a circuit breaker.

[0002] According to a first aspect of the invention there is provided a circuit breaker and a status monitor assembly which includes
   a circuit breaker housing having a circuit breaker mechanism therein; and
   a status monitor fastened to the circuit breaker housing, the status monitor including an actuating member located within the circuit breaker housing, a switch operable by the actuating member, and a set of output terminals connected to the switch, the actuating member being displaceable by a component of the circuit breaker mechanism.

[0003] The terminals are connectable, in use, to a remote status indicator, which indicates the status of the circuit breaker.

[0004] The circuit breaker housing may have an aperture into which a portion of the status monitor is insertable and the circuit breaker housing and status monitor have complementary securing formations for securing them to one another.

[0005] The status monitor may have two actuating members, two switches, and two sets of terminals, with a first actuating member being associated with one of the switches and terminal sets, and a second actuating member being associated with the other switch and terminal set. Thus, the first actuating member and associated switch may monitor the "ON" and "OFF" status of the circuit breaker; and the second actuating member and the associated switch may monitor the "LATCHED" and "TRIPPED" status of the circuit breaker.

[0006] The status monitor may have a width that is not greater than the width of the circuit breaker.

[0007] It will be appreciated that the circuit breaker and the status monitor are separate units.

[0008] Thus, according to a second aspect of the invention, there is provided a circuit breaker status monitor usable with a circuit breaker having a housing with a circuit breaker mechanism therein, to monitor its status, which includes
   an actuating member insertable into the housing;
   a switch operable by the actuating member; and
   a set of output terminals connected to the switch.

[0009] As indicated above, the actuating member may be displaceable by a component of the circuit breaker mechanism.

[0010] In particular, the actuating member may be insertable into the housing via an aperture provided therein, the aperture being located at the rear of the housing.

[0011] The circuit breaker status monitor may include a securing formation engageable with a complementary securing formation of the circuit breaker for securing the monitor to the circuit breaker.

[0012] The status the monitor may have two actuating members, two switches, and two sets of terminals, as described above. The actuating members may be levers and the switches may be mechanical microswitches.

[0013] Each actuating member may have a cam surface engageable with an associated component of the circuit breaker.

[0014] Further, according to a third aspect of the invention, there is provided a circuit breaker which has an aperture into which an actuating member of an associated status monitor may be inserted, and a mechanism which has an appropriate component having an exposed portion that is engageable, in use, by the actuating member.

[0015] Thus, as already indicated above, the aperture may be located at the rear of a housing of the circuit breaker.

[0016] The circuit breaker may have a securing formation engageable with a complementary securing formation of the monitor, for securing the monitor to the circuit breaker.

[0017] The circuit breaker may have two components with exposed portions, one being engageable with a first actuating member and the other with a second actuating member.

[0018] The invention will now be described, by way of an example, with reference to the accompanying diagrammatic drawings, in which:

Figure 1 is a side elevation of a circuit breaker and a status monitor assembly in accordance with the invention;

Figure 2 is a front view of the assembly of Figure 1;

Figure 3 is a perspective view of a circuit breaker in accordance with the invention;

Figure 4 is a perspective view of a status monitor in accordance with the invention with a portion of the housing thereof removed to illustrate internal components thereof;

Figure 5 is a side elevation of a cross-section of a first part of the status monitor of Figure 4;

Figure 6 is a side elevation of a cross-section of a second part of the status monitor of Figure 4;

Figure 7 is a side elevation of a cross-section of the circuit breaker and status monitor assembly of Figure 1.

[0019] Referring to the drawings, reference numeral 10 generally indicates a circuit breaker and status monitor assembly, in accordance with the invention. The assembly 10 comprises a circuit breaker 12 and a status monitor 14 fastened to a rear of the circuit breaker 12.

[0020] The circuit breaker 12 includes a moulded housing 16 having at its rear, an aperture 18 (see Figure 3) into which a portion of the status monitor 14 is insertable and a circuit breaker mechanism in the housing 16.

[0021] The status monitor 14 comprises a moulded housing or casing 20 which includes two parts, a first part 22 and a second part 24, and a portion 21 that is insertable into the opening 18 of the circuit breaker 12. The housing 16 and the housing or casing 20 are of a plastics material.

[0022] The first part 22 comprises a first actuating member 26 having an actuating lever 28, a microswitch 30 to monitor the "ON" and "OFF" status of the circuit breaker 12 and a set of terminals 32 connected to the microswitch 30. The second part 24 comprises a first actuating member 34 having an actuating lever 36, a microswitch 38 to monitor the "LATCHED" and "TRIPPED" status of the circuit breaker 12 and a set of terminals 40 connected to the microswitch 38. The actuating levers 28, 36, the microswitches 30, 38, the terminals 32, 40 of the first part 22 and second part 24 are separated from each other by an insulating barrier 42.

[0023] The status monitor 14 also includes a test button 44 and a passage 46 to access a terminal screw (not shown) of the circuit breaker mechanism. The test button 44 is used to actuate the microswitch 38, thus providing means for testing the "LATCHED" or "TRIPPED" circuitry of the indication circuit of the microswitch 38 without having to manually trip the circuit breaker 12. Whilst a similar arrangement may be provided for the "ON" or "OFF" microswitch 30, this is not necessary as the circuit breaker can be manually switched on and off with ease.

[0024] The actuating lever 28 of the first part 22 of the status monitor 14 has a cam profile on its front upper surface 48 which engages with a lower portion 50 of a circuit breaker handle 52 forming part of the circuit breaker mechanism to provide the "ON" or "OFF" indication function. The actuating lever 34 of the second part 24 of the status monitor 14 has a bearing surface 54, which engages with a trip lever 56 of the circuit breaker mechanism to provide the "LATCHED" or "TRIPPED" indicator function.

[0025] The circuit breaker 12 and the status monitor 14 have similar widths (Figure 2). It is to be appreciated that the assembly 10 may have a unitary housing which includes the circuit breaker 12 and the status monitor 14 assembled therein.

[0026] The circuit breaker 12 and the status monitor 14 are factory assembled. Thus the status monitor 14 is fastened onto the circuit breaker 12. In another embodiment, the circuit breaker 12 and the status monitor may be assembled in the field by an end user.

[0027] In use, the circuit breaker 12 is connected into a power supply in a conventional manner, with the microswitches 30, 38 being connected to a corresponding remote circuit breaker status indicator which indicates the "ON" or "OFF" and/or "LATCHED" or "TRIPPED" status of the circuit breaker 12. When the "ON" and/or "LATCHED" status of the circuit breaker 12 changes to "OFF" and/or "TRIPPED", the associated actuating lever 28, 36 is displaced by either the lower portion 50 of the circuit breaker handle 52 or by the trip lever 56 in the circuit breaker mechanism, activating one or both of the microswitches 30, 38 and sending a signal indicating a change in the status of the circuit breaker, to the associated remote circuit breaker status indicator (not shown) via the terminals 32, 40.

[0028] The embodiment described and illustrated with reference to the drawings has the advantage that the space required for a number of circuit breakers 12 supplied with status monitors 14, is no greater than that required for the same number of circuit breakers 12 alone.

Claims

1. A circuit breaker and a status monitor assembly which includes
   a circuit breaker housing having a circuit breaker mechanism therein; and
   a status monitor fastened to the circuit breaker housing, the status monitor including an actuating member located within the circuit breaker housing, a switch operable by the actuating member, and a set of output terminals connected to the switch, the actuating member being displaceable by a component of the circuit breaker mechanism.

2. A circuit breaker and a status monitor assembly as claimed in Claim 1, in which the terminals are connectable, in use, to a remote status indicator, which indicates the status of the circuit breaker.

3. A circuit breaker and a status monitor assembly as claimed in Claim 1 or Claim 2, in which the circuit breaker housing has an aperture into which a portion of the status monitor is insertable and the circuit breaker housing and status monitor have securing formations for securing them to one another.

4. A circuit breaker and status monitor assembly as claimed in any one of the preceding claims, in which the status monitor has two actuating members, two switches, and two sets of terminals, with a first actuating member being associated with one of the switches and terminal sets, and a second actuating member being associated with the other switch and terminal set.

5. A circuit breaker and status monitor assembly as claimed in any one of the preceding claims, in which the status monitor has a width that is not greater than the width of the circuit breaker.

6. A circuit breaker and status monitor assembly as claimed in Claim 4, in which the first actuating member and associated switch monitor the "ON" and "OFF" status of the circuit breaker.

7. A circuit breaker and status monitor assembly as claimed in Claim 4, in which the second actuating member and the associated switch monitor the "LATCHED" and "TRIPPED" status of the circuit breaker.

8. A circuit breaker status monitor usable with a circuit breaker having a housing with a circuit breaker mechanism therein, to monitor its status, which includes
   an actuating member insertable into the housing;
   a switch operable by the actuating member; and
   a set of output terminals connected to the switch.

9. A circuit breaker status monitor as claimed in Claim 8, which includes a securing formation engageable with a complementary securing formation of the circuit breaker for securing the monitor to the circuit breaker.

10. A circuit breaker status monitor as claimed in Claim 8 or Claim 9, which has a width not greater than the width of the circuit breaker housing.

11. A circuit breaker status monitor as claimed in any one of claims 8 to 10 inclusive, which has two actuating members, two switches, and two sets of terminals, with a first actuating member being associated with one of the switches and terminal sets, and a second actuating member being associated with the other switch and terminal set.

12. A circuit breaker status monitor as claimed in Claim 11, in which the first actuating member and associated switch monitor the "ON" and "OFF" status of the circuit breaker.

13. A circuit breaker status monitor as claimed in Claim 11 in which the second actuating member and associated switch monitor the "LATCHED" and "TRIPPED" status of the circuit breaker.

14. A circuit breaker status monitor as claimed in any one of claims 11 to 13 inclusive, in which the actuating members are levers and the switches are mechanical microswitches.

15. A circuit breaker status monitor as claimed in Claim 14, in which each actuating member has a cam surface engageable with an associated component of the circuit breaker.

16. A circuit breaker which has an aperture into which an actuating member of an associated status monitor may be inserted, and a mechanism which has an appropriate component having an exposed portion that is engageable, in use, by the actuating member.

17. A circuit breaker as claimed in claim 15, which has a securing formation engageable with a complementary securing formation of the monitor, for securing the monitor to the circuit breaker.

18. A circuit breaker as claimed in Claim 15, in which the aperture is located at the rear of a housing of the circuit breaker.

19. A circuit breaker as claimed in Claim 15, which has two components with exposed portions, one being engageable with a first actuating member and the other with a second actuating member.

20. A circuit breaker and a status monitor assembly, substantially as herein described and illustrated.

21. A circuit breaker status monitor, substantially as herein described and illustrated.

22. A circuit breaker, substantially as herein described and illustrated.

Drawing