480 V switchboard workhorse
The Siemens SENTRON 3VA2450-7KP42-0AA0 is a 4-pole molded case circuit breaker rated for 500 A continuous current, built around the ETU850 electronic trip unit. It's a line-protection device — meaning it sits upstream of distribution or motor loads and clears faults fast. The interrupting ratings tell the story: 330 kA at 240 V, 242 kA at 415 V and 440 V, 187 kA at 500 V, and still 9 kA at 690 V. That's serious fault-current headroom for a 500 A frame, so you can count on selectivity downstream without worrying about cascade failure on a high-SCCR bus.
Thermal derating and panel fit
The breaker holds full 500 A rating up to 50 °C ambient, then derates to 477 A at 55 °C, 455 A at 60 °C, 432 A at 65 °C, and 410 A at 70 °C. Max power loss is 99 W — factor that into your enclosure ventilation if you're packing several breakers in a row. Dimensions: 248 mm tall, 184 mm wide, 110 mm deep. That's a standard MCCB footprint for a 4-pole frame this size; it'll drop into most SENTRON panelboards without re-drilling.
Trip unit and communication
The ETU850 electronic trip unit gives you adjustable N-conductor protection (OFF, 20% to 100%) and communication capability — so it can talk to a BMS or a plant SCADA for power monitoring and remote trip coordination. The latching endurance is 15 000 cycles, which is typical for a solid-frame MCCB in distribution duty. If you're comparing against the 5SQ2670-2YA63 or similar 500 A frames, the ETU850's programmability and comms integration are the differentiators; the 5SQ series is a simpler thermal-magnetic design without the communication module.