Arc fault detection breaker for final subcircuits
The Schneider Electric A9TPE4640 is an Acti9 iC40 ARC arc fault detection circuit breaker (AFDD) rated 40 A, 1P+N, C-curve. It combines thermal-magnetic overcurrent protection with series arc fault detection in a single 36 mm wide DIN-rail module, intended for outgoer circuits in residential and commercial final distribution boards. Rated breaking capacity is 3000 A Icn per EN/IEC 60898-1 and 10 kA Icu per EN/IEC 60947-2 at 230 V AC, 50 Hz — sufficient for most final subcircuit fault levels in TN and TT systems.
What the arc fault detection adds
Unlike a standard MCB, this device includes series arc fault detection per EN/IEC 62606. It monitors the waveform for high-frequency noise and current asymmetry characteristic of arcing faults — loose connections, damaged conductors, or carbonised insulation — and trips before the fault escalates to fire. The local signalling (ON, OFF, fault trip LED) gives a clear visual indication of an arc fault trip, which helps the commissioning engineer distinguish it from an overload or short-circuit event. Tropicalisation severity B per IEC 60068-2-30 (28-day damp heat cycling) and pollution degree 2 rating mean the internal tracking paths are designed for high-humidity environments — relevant for coastal or unconditioned electrical rooms where standard breakers may see nuisance arc detection from condensation.
Clip-on mounting to standard 35 mm DIN rail, 36 mm width (4 × 9 mm pitches). Tunnel terminals accept 1–16 mm² rigid or 1–10 mm² flexible cable; wire stripping length 14 mm, tightening torque 2 N·m. Cable entry from top and bottom, neutral on the left side. The 73 mm depth leaves clearance behind most standard enclosure gland plates. IP20 finger-safe terminals per IEC 60529; suitable for installation in distribution boards with IP4X or higher enclosure rating. Operating altitude limited to 2000 m — above that, dielectric withstand and breaking capacity derate per IEC 60947-2 annex R.