Interlock Application Scheme # 13 - Prevent Paralleling of Lines

Contents | Introduction | Symbols Legend | Scheme Book

Interlock Application - Prevent Paralleling of Lines

Scheme # 13
To prevent paralleling of lines A and B. Two loads, fed from either source.

Interlock Application Scheme # 13 - Preven Paralleling of Lines

Breaker A is closed to supply load M. Breaker B is closed to supply load N. Tie-breaker C is open. Keys A-1 are held in interlocks on both breakers A and B. Tie-breaker C cannot be closed unless either A or B is locked open.

To transfer load N to breaker A:

1.
2.

3.

4.

Open breaker B.
Turn key A-1 in L-O interlock on breaker B to lock open. Key A-1 is now free.
Insert key A-1 in L-O interlock on tie-breaker C and turn to unlock. Key A-1 is now held.
Close tie-breaker C.

Reverse sequence to restore service.

Load M can be supplied through breaker B in a similar manner.

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