The Siemens SENTRON 5SV3326-4 is a 2-pole Type B residual current circuit breaker (RCCB) rated 63 A with a 30 mA trip threshold, designed for 230 V AC supply. The Type B characteristic means it detects smooth DC residual currents in addition to AC and pulsed DC — critical for variable-speed drives, UPS systems, and PV inverters that can generate DC fault currents a standard Type A or AC device would miss. The short-time delayed (S-type) selectivity prevents nuisance tripping when downstream devices clear a fault first, making it suitable for sub-distribution boards feeding multiple circuits.
The 30 mA sensitivity (IΔn) provides personal protection against direct contact; at 63 A continuous rating, it handles the full load of a submain feeding a workshop or a small production line.
The 70 mm installation depth matches standard distribution board clearances. Supply can be fed from top or bottom; the SIGRES function (a Siemens feature) keeps the device powered for testing even in the switched-off state when fed from the top.