What this RCCB is and what it does
The Siemens 5SV3322-4 is a 2-pole residual current operated circuit breaker (RCCB) from the SENTRON series, rated 25 A with 30 mA sensitivity, Type B, short-time delayed, for 230 V AC at 50/60 Hz. Type B detection means it catches AC sinusoidal residual currents, pulsating DC, and smooth DC up to the rated sensitivity — critical for drives, UPS systems, and PV inverters that can generate DC fault currents a standard Type A would miss. The short-time delayed design (SIGRES function) prevents nuisance tripping from transient surge currents or inrush from downstream equipment, making it suitable for feeder circuits where selectivity with downstream RCCBs is required.
Mounting and panel fit
Snaps onto DIN rail (REG) — standard 35 mm rail in any mounting position. Occupies 4 modular width units (72 mm wide) at 60 mm grid spacing. Depth is 70 mm, matching the installation depth. IP20 with connected conductors in an installed distribution board — intended for enclosed panel use, not open washdown areas. Supply can enter from top or bottom; the SIGRES function remains active even in the switched-off state when fed from the top.
Ratings and what they mean for your circuit
Rated short-circuit current (SCCR) is 10 kA per IEC 61008-1 — the device can safely interrupt a fault current up to 10 kA without welding contacts or causing external flash. The series fuse maximum permissible is 100 A for backup protection. Power dissipation is 1.2 W per pole in hot operating state at rated current — low enough to avoid derating concerns in a densely packed DIN rail enclosure, but still worth summing across all poles for thermal budget. Mechanical service life is 10,000 operating cycles typical — adequate for distribution panel duty where the RCCB is operated infrequently (monthly test or fault reset). Ambient operating range -25 °C to +45 °C; storage down to -40 °C. Overvoltage Category III — suitable for fixed installation downstream of the service entrance.
Lifecycle and sourcing
Silicon-free construction matters for automotive paint-shop or semiconductor fab environments where silicone outgassing can contaminate surfaces.