What this 500 A MCCB delivers
The Siemens 3VA2450-6KQ42-0AA0 is a SENTRON molded case circuit breaker rated for line protection in 4-pole configuration. It carries a continuous current Iu of 500 A at 40 °C, with full 500 A rating holding through 50 °C — no derating needed in a typical 40 °C panel ambient. At 55 °C it's still good for 477 A, and at 70 °C it delivers 410 A, so you can push the ambient without losing the main bus rating. Breaking capacity is the headline: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 9 kA at 690 V. That 242 kA at 240 V is the highest short-circuit rating in the 3VA2 family — sized for high-fault utility feeds or transformer secondaries where SCCR headroom is non-negotiable. The ETU860 electronic trip unit handles overcurrent protection with ground-fault monitoring via summation current formation on L + N. Communication function is built in, so you can integrate status and trip data into a BMS or plant SCADA without an add-on module.
Panel fit and environment
Dimensions are 248 mm high, 184 mm wide, 110 mm deep — a 4-pole frame that fits standard SENTRON mounting patterns. Front IP40 protection handles the panel interior; no washdown rating, so keep it behind a gland plate or enclosure door. Operating temperature range is -25 °C to 70 °C, storage from -40 °C to 80 °C. Max power loss is 99 W, which matters for thermal budgeting inside a sealed enclosure — account for that heat when sizing ventilation or cooling.