The Schneider Electric A9Z35480 is a 4-pole residual current circuit breaker (RCCB) from the Acti9 iID family, rated 80 A continuous with 300 mA earth-leakage sensitivity. The 4P configuration (switching all four poles, neutral left) means it protects three-phase circuits with a neutral conductor, common for 380-415 V AC networks at 50/60 Hz. The Type A-SI (Super Immunised) designation means this RCCB handles pulsed DC residual currents from single-phase rectifiers (typical in VFDs, UPS, and LED drivers) while rejecting nuisance trips from high-frequency leakage. The selective (time-delayed) characteristic — the S in A-SI — coordinates with downstream RCCBs so only the faulted branch trips, keeping the rest of the board live. That matters on a conveyor line or process skid where a single ground fault shouldn't drop the whole panel.
80 A rated current (In) at 380-415 V AC matches the main incoming feed for a moderate-sized sub-distribution board — think a panel feeding several motor starters or a mix of lighting and socket circuits. Voltage-independent trip technology means the RCCB detects earth leakage and disconnects even if the phase voltage collapses — the trip energy comes from the fault itself, not from an external supply. That's a reliability advantage in brownout or lost-neutral conditions. The 8/20 µs impulse withstand of 3000 A (per EN/IEC 61008-1) confirms it survives surge events without false tripping, relevant on industrial lines with welding gear or large motor starts nearby.
Installation and wiring
The IP20 body (IP40 in a modular enclosure) is fine for dry indoor panels — not for washdown zones without a separate enclosure.