RCCB for 4-wire systems, Type A sensitivity
The Siemens 5SM3646-6BA is a 4-pole residual current circuit breaker (RCCB) from the SENTRON family, rated 63 A at 400 V AC with a 300 mA trip threshold and Type A residual current sensitivity. Type A detection covers sinusoidal AC fault currents plus pulsating DC fault currents — the standard for circuits with single-phase rectifiers, switching power supplies, or variable-speed drives downstream. The 10 kA short-circuit current rating (SCCR) means it safely interrupts faults up to that level without upstream damage, sized for distribution boards in commercial and industrial installations.
Mounting and panel integration
Snaps onto DIN rail (REG) per, occupying 4 modular width units (4 MW) at a 70 mm installation depth. Mounting position is any orientation, and supply can enter from top or bottom — useful when retrofitting into an existing distribution board where busbar routing is fixed. IP20 with conductors connected, so it lives inside a closed panel or distribution box, not exposed to washdown.
Ambient limits and storage range
Operating ambient spans -25 °C to 45 °C; storage extremes are -40 °C to 75 °C. The storage range governs handling and warehousing, not running — the part can sit in an unheated warehouse but must be within the narrower operating band when energized under load.