Interlock Application Scheme # 5- Isolating Switches and Breaker

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Interlock Application - Isolating Switches and Breaker

Scheme # 5
To prevent operation of disconnect switch A when breaker B is closed. To prevent opening fuse compartment door when the disconnect switch A is closed.

Interlock Application Scheme # 5 - Isolating Switches and Breaker

Breaker, fuse compartment door and disconnect switch are shown in closed positions. Key A-1 is held in breaker interlock and key A-2 is held in disconnect interlock.

To service breaker:

1.
2.

3.

4.
5.

6.

Open breaker.
Turn key A-1 in L-O interlock on breaker to lock breaker open. Key A-1 is now free.
Insert key A-1 in L-O-C interlock on disconnecting switch and turn to unlock. Key A-1 is now held.
Open disconnect.
Turn key A-1 in L-O-C interlock on disconnect switch to lock open. Key A-1 is now free.
Return key A-1 to breaker interlock and unlock for operation of breaker during servicing.

Reverse sequence to restore service.

To open fuse compartment door:

1.

2.

3.

4.

Proceed from normal position with operations as in 1 through 4 above.
Turn key A-2 in L-O interlock on disconnect switch to lock open. Key A-2 is now free.
Insert key A-2 in L-C interlock on fuse compartment door and turn to unlock. Key A-2 is now held.
Open fuse compartment door.

Reverse sequence to restore service.

Links for more interlock application scheme information:

Contents | Introduction | Symbols Legend | Scheme Book

Scheme # 1
Scheme # 2
Scheme # 3
Scheme # 4
Scheme # 5
Scheme # 6
Scheme # 7
Scheme # 8
Scheme # 9
Scheme # 10
Scheme # 10A
Scheme # 11 Scheme # 12

Scheme # 13
Scheme # 14
Scheme # 15
Scheme # 16
Scheme # 17
Scheme # 17A Scheme # 18
Scheme # 19
Scheme # 20
Scheme # 21
Scheme # 22 Scheme # 23
Scheme # 24

Scheme # 25
Scheme # 26
Scheme # 27 Scheme # 28
Scheme # 29
Scheme # 30
Scheme # 31
Scheme # 32
Scheme # 33 Scheme # 34
Scheme # 35
Scheme # 35A
Scheme # 36

Scheme # 37
Scheme # 38 Scheme # 39
Scheme # 40
Scheme # 41
Scheme # 42
Scheme # 42A
Scheme # 42B
Scheme # 43
Scheme # 43A
Scheme # 44
Scheme # 45
Scheme # 45A