Basic steps for calculating the SCCR of a control panel
4.2 SB4.3 – Adaptation of the available short-circuit current rating based on the peak let-through currents when
using current-limiting devices in the feeder circuit
Short-circuit current rating (SCCR) of industrial control panels
22 Reference Manual, 06/2013, A5E31896849002A/RS-AA/001
⇒ SCCR 50 kA since the breaking capacity of the circuit breaker is not lower than that of the
fuse.
The contactor and overload relays are protected by the fuse in the feeder circuit since 5 kA
(SCCR of contactor and overload relays) is > 3 kA (let-through value of the fuse).
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