Residual current circuit breaker, Type A, 40 A, 100 mA, short-time-delayed G
The Siemens 5SV3444-6MJ01 is a residual current operated circuit breaker (RCCB) Type A, rated 40 A with a 100 mA residual sensitivity, 3+N-pole, 400 V, and a 10 kA short-circuit capacity. The short-time-delayed G characteristic means it tolerates brief surge currents (e.g., from connected electronics or lightning) without nuisance tripping — suited for circuits with capacitive inrush or where selective coordination with downstream devices is needed.
The 40 A rating governs the continuous load current the RCCB can carry without thermal tripping — sized for a 40 A feeder or submain. The 100 mA residual sensitivity is higher than the standard 30 mA personal-protection threshold; this unit is intended for equipment or fire protection where a higher trip level avoids nuisance tripping on leakage from long cable runs or multiple loads. The 3+N-pole configuration switches all three phases and the neutral, with the neutral pole switched (not just solid). The short-time-delayed G characteristic provides a deliberate delay (typically 10–40 ms) to ride through transient surges, enabling selective coordination with downstream 30 mA RCCBs.
The 3+N-pole wiring accepts incoming three-phase and neutral; the outgoing terminals feed the protected circuit. The short-time-delayed G characteristic makes it a natural choice as an incoming or submain RCCB in a selective coordination scheme, where downstream 30 mA RCCBs clear earth faults first and this unit holds in during the transient.