What this MCCB delivers
The Siemens 3VA2340-5HL42-0HC0 is a SENTRON molded case circuit breaker rated for 400 A continuous current at 40 °C through 50 °C, with thermal derating to 340 A at 70 °C. Its 4-pole configuration and line protection design make it a direct fit for main or feeder breaker duty in distribution panels. Short-circuit ratings hit 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 7.5 kA at 690 V — giving you selectivity headroom across common industrial voltage levels. The breaker ships with a shunt trip (STL) auxiliary release and two HQ auxiliary switches built in, plus a voltage trigger indicator. The basic switch is order code 3VA2340-5HL42-0AA0.
Panel fit and thermal planning
Footprint is 184 mm wide by 248 mm tall by 110 mm deep — a standard 4-pole MCCB envelope for DIN-rail or panel-mount integration. The 96 W maximum power loss at full rating needs ventilation consideration in sealed enclosures. Operating temperature range spans -25 °C to 70 °C, with storage from -40 °C to 80 °C. The continuous current holds flat at 400 A up to 50 °C, then derates linearly to 340 A at 70 °C — plan your ambient accordingly.