GE EntelliGuard G Application Manual page 38

Section 4. Accessories
Table 4.15
Interlock Configurations
Typical Circuit
B1
B1 B2
B1 B2
B1 B2
36
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Interlock Configuration
Type A
1 from 2 way interlock
G
2 cable configuration
Interlocking between 2 circuit breakers
B2
1 normal power supply
1 generator (emergency) supply
Type B
1 from 3 way interlock
G
6 cable configuration
Interlocking among 3 circuit breakers
3 power supplies (generator or transformers)
B3
feeding the same busbar but parallel
operation is prevented.
Available on request
Type C
2 from 3 way interlock
6 cable configuration
G
Interlocking among 3 circuit breakers
2 bus sections can be powered by single
transformer (bus coupler closed) or both
B3
transformers (bus coupler open).
Available on request
Type D
1 from 3 way interlock variant
G
4 cable configuration (2 cable for bus coupler)
Interlocking among 3 circuit breakers
B3
2 normal power supplies not set in parallel
1 power supply may assist the priority circuit
Available on request
Type E
2 from 3 way "specific" interlock
4 cable configuration
Interlocking among 3 circuit breakers
2 normal power supplies can be set in parallel
1 generator (emergency) supply
Available on request
Possible Combinations
B1 B2
O O
I O
O I
Circuit breaker B1 can close only if B2 is open
Circuit breaker B2 can close only if B1 is open
B1 B2
O O
I O
O I
O O
Only 1 of 3 breakers can be closed
B1 B2
O O
I O
O O
O I
I I
O I
I O
Any 2 from 3 breakers can be closed
Any 1 from 3 breakers can be closed
2 breakers must be closed to prevent
the 3rd breaker from closing
B1 B2
O O
I O
O O
I O
O I
Circuit breaker B1 and/or B3 can be closed
only if B2 is open
Circuit breaker B2 can only be closed if B1
and B2 are both open
B1 B2
O O
I O
O I
I I
O O
B3
O
O
O
I
B3
O
O
I
O
O
I
I
B3
O
O
I
I
O
B3
O
O
O
O
I