The A9Z24425 is a Schneider Electric Acti9 iID residual current circuit breaker (RCCB) — a 4-pole, 25 A device with 300 mA Type A earth-leakage sensitivity, rated for 380...415 V AC networks at 50/60 Hz. It uses voltage-independent residual current tripping, so it clears ground faults without relying on the supply voltage to power its electronics; the trip coil is energized directly by the fault current itself.
The 25 A continuous rating (In) is the load current the RCCB carries in normal service; the 300 mA sensitivity means it will trip when the leakage to earth exceeds that threshold. For a panel feeding mixed loads (lighting, small drives, control transformers), Type A is the standard choice; a pure AC-only Type AC would miss pulsating DC faults. Rated conditional short-circuit current is 10 kA (IEC 61008-1), meaning the RCCB can withstand a 10 kA fault without rupturing, provided an upstream overcurrent device (MCB or fuse) clears the fault within its let-through rating. The breaking capacity Idm is 1500 A — the maximum fault current the RCCB itself can interrupt. In practice, the 10 kA SCCR is the figure that governs coordination with the upstream breaker in a distribution board.
Clip-on mounting to a 35 mm DIN rail, 4-pole wide (72 mm, 8 x 9 mm pitches). Neutral is on the left. The toggle control and padlocking provision are standard for lockout/tagout on the panel door.