The Schneider Electric A9KR13440 is a 4-pole residual current circuit breaker (RCCB) from the Acti9 ID K series, rated at 40 A with 30 mA earth-leakage sensitivity. The 40 A continuous rating and 380-415 V AC operational voltage size it for group incomer duty or submain protection where the load is balanced across three phases plus neutral. If your downstream equipment includes VFDs, switched-mode supplies, or LED drivers that generate pulsed DC fault currents, you need a Type A or Type B RCCB instead. This part is instantaneous, so it trips without intentional delay; selectivity against downstream RCCBs requires a time-delayed (S-type) device.
Clip-on mounting onto standard DIN rail — 8 modules wide at 9 mm pitch, so it occupies 72 mm of rail width. Neutral is on the left. The biconnect terminals accept 1-35 mm² rigid or 1-25 mm² flexible cable, top or bottom, with a tightening torque of 3.5 N.m. Strip length is 14 mm.
Designed to EN/IEC 61008-1 and SS 97:part 1. Carries the SAFETY Mark quality label. Tropicalisation class 2 per IEC 60068-1 — suitable for ambient storage from -25 to 85 °C and 95 % relative humidity at 55 °C. Pollution degree 2. The 8/20 µs impulse withstand rating of 200 A confirms immunity to common surge shapes without nuisance tripping.