The Schneider A9N21493 is a Prodis Vigi TG40 add-on residual current device — a 3P+N block rated 40 A with 300 mA earth-leakage sensitivity, Type AC, voltage-independent trip. Rated operational voltage is 400 V AC phase-to-phase at 50 Hz, with an insulation voltage of 400 V AC and impulse withstand of 6 kV per EN 61009-1. The 300 mA sensitivity is instantaneous — no time delay — so it clears ground faults immediately on detection. Pollution degree 3 and tropicalisation class 2 (per IEC 60068-1) qualify it for damp, non-condensing environments up to 95 % RH at 55 °C. Altitude limit is 2000 m.
Schneider has marked the A9N21493 as obsolete.
Screw terminals accept rigid cable 0.75…16 mm² or flexible 0.33…10 mm²; strip length 13 mm, torque to 2 N·m. Electrical connection to the upstream MCB is by screws — this is a mechanical and electrical add-on, not a standalone device. The 9 mm pitch occupies 6 pitches on the DIN rail. Local ON/OFF indication on the block face aids troubleshooting.
Designed to IEC 60947-2, EN 61009-1, and EN 61009-2-1. The voltage-independent trip mechanism ensures operation even if the neutral is lost upstream, a key reliability feature for group incomer protection.