DET-653C
EntelliGuard
®
G Circuit Breaker Application Guide
24-May-12
Section 4. Accessories
©2012 General Electric All Rights Reserved
46
Table 4.20. Interlock Configurations
Typical Circuit
Interlock Configuration
Possible Combinations
Type A
1 from 2 interlock
2 cable configuration
Interlocking between two circuit breakers
One normal power supply
One generator (emergency) supply
B1
B2
O
O
1
O
O
1
B1 can close only if B2 is open.
B2 can close only if B1 is open.
Type B
1 from 3 interlock
6 cable configuration
Interlocking among three circuit breakers
Three power supplies (generator or transformers)
feeding the same busbar but parallel operation is
prevented.
Available on request.
B1
B2
B3
O
O
O
1
O
O
O
1
O
O
O
1
Only 1 of 3 breakers can be closed.
Type C
2 from 3 interlock
6 cable configuration
Interlocking among three circuit breakers
Two bus sections can be powered by single
transformer (bus tie breaker closed) or both
transformers (bus tie breaker open).
Available on request.
B1
B2
B3
O
O
O
1
O
O
O
O
1
O
1
O
1
1
O
O
1
1
1
O
1
•
Any two from three breakers can be closed.
•
Any one from three breakers can be closed.
•
Two breakers must be closed to prevent the
third breaker from closing.
Type D
1 from 3 interlock
6 cable configuration
Interlocking between three circuit breakers
Two normal power supplies cannot be connected
in parallel. One power supply may assist the
priority circuit.
Available on request.
B1
B2
B3
O
O
O
1
O
O
O
O
1
1
O
1
O
1
O
•
B1 and/or B3 can be closed only if B2 is open.
•
B2 can only be closed if B1 and B2 are both
open.
•
Contact factory for availability.
