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. That 187 kA figure tells you this breaker is sized for high-fault locations like main switchboards or transformer secondaries where available fault current is substantial.
Dimensions and panel integration
The breaker measures 248 mm high, 184 mm wide, and 110 mm deep — a 4-pole footprint that fits standard SENTRON 3VA panel cutouts. At 110 mm depth, it clears most 200 mm deep enclosures with room for rear busbar connections. The 63.5 W maximum power loss at rated load means ventilation slots or a moderate thermal budget in the enclosure; plan for that heat in a sealed cabinet.
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. No trip indicator, no undervoltage release, and no communication module on this order code. It is a line-protection design, meaning the trip curve is optimized for feeder and main breaker duty rather than motor or generator protection.