Application planning
4.3 Communication planning
3VA27 molded case circuit breakers & 3WL10 air circuit breakers
Manual, 10/2018, L1V30499596002-01
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4.2.3
Armature plates
The electrodynamic forces that arise during a short-circuit can result in high mechanical
loads in and on the switchboard. To minimize the effects, armature plates must be mounted
in the vicinity of the terminals of the circuit breaker.
Busbars
The following diagram shows the distance of the first armature plate depending on the
prospective short-circuit current when busbars are used:
①
Distance of the first armature plate to the terminals of the circuit breaker
②
Prospective short-circuit current
Cables
If cables are used in the installation, the armature plates must be mounted at a distance of
150 mm from the connection.