The Schneider Electric A9Z24280 is an Acti9 iID residual current circuit breaker (RCCB) — a voltage-independent, 2-pole device rated for 80 A continuous load at 220-240 V AC, 50/60 Hz. It trips on earth-leakage faults at 300 mA sensitivity, Type A waveform detection, meaning it catches pulsating DC residual currents from rectified loads like VFDs, switching power supplies, and LED drivers. The 300 mA threshold is typical for circuit protection where a 30 mA unit would nuisance-trip on normal leakage from long cable runs or filter caps.
The 80 A rated current (In) sets the continuous load limit through the main contacts — sized for a submain feeder or a large single load, not a final subcircuit. The 300 mA earth-leakage sensitivity is an equipment-protection or fire-protection threshold, not personnel protection (that would be 30 mA or lower). Type A detection means it sees the pulsating DC waveforms common in modern electronic loads; a plain AC-type RCCB would miss those and leave the fault live. Breaking capacity: Idm 1500 A and Im 1500 A — this is the RCCB's own fault-clearing capability for earth faults. The conditional short-circuit rating is 10 kA (IEC 61008-1), meaning it can withstand a 10 kA prospective fault current when backed by an upstream overcurrent device (MCB or fuse) sized per the manufacturer's coordination table. Without that backup, the RCCB's own contacts are rated for 1500 A make-break. Impulse withstand: 8/20 µs surge, 250 A — this is the electromagnetic compatibility rating per EN/IEC 61008-1. It tells you the RCCB will not nuisance-trip on a lightning or switching surge up to that energy.
Neutral on the left. The double-terminal design accepts up to 35 mm² rigid on the front, 25 mm² flexible with ferrule — enough for the 80 A feed conductors. Torque terminals to 3.5 N·m. Strip length 14 mm.