Technical data

IZMX circuit-breakers, INX switch-disconnectors
Mechanical Interlock configurations
CA01305001Z-EN www.eaton.com
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Mechanical Interlock configurations
Type of interlock Typical circuit Interlocks possible
Mechanical Interlock configurations
Type 2
Across Two Circuit Breakers
One normal power supply and one
emergency power supply.
Circuit breaker A can only be
closed if B is open and vice versa.
A = Normal power supply.
B = Emergency power supply.
AB
00
10
01
Interlock: A against B
Type 31
Across Three Circuit Breakers
Two normal power supplies and
one emergency power supply.
Circuit breaker A and C can only be
closed if B is open. B can only be
closed when A and C are open.
ABC
000
100
010
001
101
Interlock: A, C against B
Type 32
Across Three Circuit Breakers
The two half-bus bars can be pow-
ered by a single transformer (bus-
tie closed) or by both at the same
time (bus-tie open).
One of two circuit breakers out of
three can be closed at the same
time.
ABC
000
100
010
001
110
011
Interlock: 2 against 1 or max. 2 of 3 1 0 1
Type 33
Across Three Circuit Breakers
Three power supplies (generators
or transformers) on the same bus
bar, making operation in parallel
impossible.
Only one of three circuit breakers
can be closed.
ABC
000
100
010
001
Interlock: 1 against 2 or max. 1 of 3
A
TR
B
AB
TR1 TR2
C
AB
TR1 TR2
C
AB
TR1
C
IZMX16, INX16, IZMX40, INX40