The Siemens 5SV3646-8MJ is a residual current operated circuit breaker (RCCB) Type A, rated 63 A with a 300 mA trip sensitivity, 10 kA breaking capacity, 3+N-pole configuration, and 400 V operating voltage. It is a selective (S-type) device, meaning it has a deliberate time delay to coordinate with downstream RCCBs — the upstream unit holds during a fault on a branch, so only the closest breaker trips, keeping the rest of the distribution live.
Deployment context
This is a DIN-rail mounted RCCB for distribution boards in commercial and industrial installations. The 300 mA sensitivity and Type A waveform detection (sinusoidal AC plus pulsating DC fault currents) suit it for circuits with electronic loads — VFDs, switched-mode power supplies, UPS systems — where pure AC detection would miss half-wave fault currents.