Line protection MCCB, 400 A frame, 4-pole
The Siemens SENTRON 3VA2340-5HN42-0AE0 is a 4-pole molded case circuit breaker (MCCB) rated for 400 A continuous at 40 °C, designed for line protection in distribution panels. Its 187 kA breaking capacity at 240 VAC gives substantial fault-current headroom for service-entrance or main feeder applications where available short-circuit current runs high. At 415 VAC the interrupt rating holds at 121 kA, so it handles industrial 400 V distribution without cascading upstream breakers in most configurations. The 400 A frame carries full rated current through 50 °C ambient; above that it derates linearly to 340 A at 70 °C. That thermal curve matters when the breaker sits in a crowded enclosure with other heat sources — the 96 W maximum power loss at rated load adds to the internal heat rise, so panel builders should account for it in the thermal budget.
Breaking capacity by voltage level
This MCCB delivers 187 kA at 240 VAC, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 7.5 kA at 690 V. The steep drop at 690 V is typical for a 400 A frame — the arc energy at that voltage limits what a compact interrupter can clear. For 690 V feeders, confirm the available fault current stays under 7.5 kA or step to a higher-frame breaker.
Panel fit and auxiliary configuration
Dimensions are 248 mm high, 184 mm wide, 110 mm deep — a standard 4-pole MCCB footprint that drops into SENTRON mounting plates and DIN-rail adapters. The breaker ships without an undervoltage release or ground-fault monitoring module; those are field-addable options if the application requires shunt-trip or GF protection. The four HQ auxiliary switches provide status feedback for PLC inputs or remote indication without needing a separate accessory.