Applications
3.4 Use of 3VA1 molded case circuit breakers as switch disconnectors
3VA molded case circuit breakers with IEC certificate
170
Manual, 03/2019, A5E03603177010-03
3.4.2
Upstream protection of switch disconnectors
Switch disconnectors are not equipped with an integral overload or short-circuit release. For
this reason, a molded case circuit breaker or a fuse must be installed upstream of every
switch disconnector.
The coordination tables given below contain the following information:
●
The correct assignment of molded case circuit breakers to the switch disconnectors which
require protection
●
The maximum permissible rms short-circuit current kA rms for each combination of
molded case circuit breaker and switch disconnector
Protection of 3VA1 switch disconnectors at 50 / 60 Hz by a 3VA1 molded case circuit breaker
More combinations can be found on the Internet (