What this 500 A MCCB delivers — and where the ratings matter
The Siemens SENTRON 3VA2450-6JQ42-0AA0 is a 4-pole molded case circuit breaker rated for 500 A continuous current at 40 °C ambient, with an ETU560 electronic trip unit configured for line protection. Its interrupting capacity reaches 242 kA at 240 V AC, 187 kA at 415 V, 85 kA at 440 V, 55 kA at 500 V, and 9 kA at 690 V — which means at typical 400 V distribution voltages it clears fault currents up to 187 kA without upstream coordination issues. The rated insulation voltage is 800 V, so it suits 690 V line-to-line systems with margin. Thermal derating is published per the datasheet: the breaker holds 500 A through 50 °C, then drops to 477 A at 55 °C, 455 A at 60 °C, 432 A at 65 °C, and 410 A at 70 °C. If your panel ambient runs above 50 °C, size the load current against the derated figure — not the 500 A nameplate.
Panel integration and footprint
The breaker measures 184 mm wide, 248 mm tall, and 110 mm deep. Front protection is IP40, so it is suited for enclosed panel mounting where the front face is behind a door or cover. The ETU560 release supports communication functions, which allows remote monitoring and trip-data retrieval via the SENTRON communication bus.