The A9V21263 is a voltage-independent, add-on residual current device (RCD) from the Acti9 Vigi iC60 range, designed to snap onto the side of a compatible iC60 MCB. It adds earth-leakage protection to that circuit without needing a separate power supply for the trip coil — the trip energy comes from the fault itself, so it still clears a line-to-ground fault even if the neutral is lost. Rated 63 A continuous, with a 30 mA sensitivity, Type A (pulsating DC and sinusoidal AC leakage), and instantaneous trip. That means it catches both pure AC faults and the pulsed DC waveform from downstream electronics — rectifiers, VFDs, switched-mode supplies — common on modern panels. The 30 mA threshold is the standard for personal protection against electric shock. The screw terminals torque to 3.5 N·m. Strip length is 14 mm for the bottom connection.
The 8/20 µs impulse withstand of 250 A (per IEC 61009-1) means the internal sense coil can handle a lightning-induced surge without saturating or nuisance-tripping. This is a practical spec for outdoor-fed residential or light commercial boards.
Clip-on mounting to DIN rail. The module is 72 mm wide (4 pitches), 91 mm tall, 73.5 mm deep. It sits on the outgoing side of the MCB, mechanically linked via screws — so it shares the same busbar and occupies the same DIN-rail footprint as the breaker. IP20 on the front (finger-safe), IP40 inside a modular enclosure. Fine for a clean panel; if the board is in a washdown area, you'll need an outer cabinet. The storage range is wider — that's the shipping and shelf-life limit, not the running limit.