400 A MCCB with 187 kA interrupting capacity — panel fit and trip logic
The Siemens SENTRON 3VA2440-5HL42-0AA0 is a 4-pole molded case circuit breaker rated for 400 A continuous current across the full 40 °C to 70 °C ambient range — no derating needed up to that ceiling. Its ETU320 electronic trip unit handles the overload and short-circuit protection curve, with a maximum breaking capacity of 187 kA at 240 V and 121 kA at 415 V.
The breaker measures 248 mm high, 184 mm wide, and 110 mm deep — a 4-pole footprint that fits standard SENTRON 3VA panel cutouts.
Trip unit and protection logic
The ETU320 overcurrent release is a microprocessor-based trip unit with adjustable long-time, short-time, instantaneous, and ground-fault protection bands — though this variant ships without ground-fault monitoring. It is a line-protection design, meaning the trip curve is optimized for feeder and main breaker duty rather than motor or generator protection.