Accessories
4.7 Locking and interlocking
3VA molded case circuit breakers
Manual, 04/2015, A5E03603177010-02
271
Principle of two mutually interlocked 3VA molded case circuit breakers:
Molded case circuit breaker blocked/locked in the safe switching state OFF (O)
Molded case circuit breaker released for operation
The following interlocking systems are available for 3VA molded case circuit breakers:
● Front interlock
● Rear interlock
All front interlocks are installed on the front panel of the 3VA molded case circuit breaker.
Front interlocks make it impossible to install some other external accessories such as motor
operator, rotary operators, etc. They also partially restrict access to internal accessories
compartments.
The rear interlock does not affect the front panel of the 3VA molded case circuit breaker. All
components of the interlocking system are concealed behind the molded case circuit breaker
or the mounting plate.