The Schneider Electric C40L4 is a ComPacT NSX400L basic frame — a 4-pole, 400 A frame rated at 40 °C, designed for distribution applications. It carries a 150 kA Icu at 415 V AC (breaking capacity code L), with an Ics of 150 kA at 380/415 V AC, meaning it can repeatedly interrupt fault currents up to that level without needing replacement after a single event — a real advantage for high-fault locations like main switchboards or feeder breakers in industrial plants.
Mounts fixed to a backplate (not DIN rail) — the 185 mm width, 255 mm height, and 110 mm depth fit standard ComPacT NSX cutouts. Front connection on both line and load sides; neutral is left-positioned. The toggle control and IP40 front face (IK07 impact resistance) suit enclosed panel installation where accidental contact is a concern. Pollution degree 3 and overvoltage category III mean it is rated for industrial environments with conductive pollution and transient overvoltages up to 8 kV impulse withstand.
Rated insulation voltage 800 V AC, operational voltage 690 V AC. Electrical durability: 12,000 cycles at 440 V AC at In/2, 6,000 cycles at In. Mechanical durability 15,000 cycles. Suitable for isolation per EN/IEC 60947-2 — the open contacts provide a visible break. Class II insulation on the front face adds operator touch-safety. Operating temperature range -25 to 70 °C; storage -50 to 85 °C — runs cold and stays cold even in unheated warehouses.