Line protection MCCB with shunt trip
The Siemens SENTRON 3VA1050-4ED32-0KA0 is a 3-pole molded case circuit breaker rated for line protection, carrying 50 A continuous at 40 °C and holding that rating up to 50 °C before derating to 48 A at 55 °C and 45 A at 70 °C. The TM210 thermal-magnetic release handles overload and short-circuit protection; the integrated shunt trip (order code 3VA9688-0BL33) allows remote tripping via a control signal. Breaking capacity runs 121 kA at 240 V AC, 75.6 kA at 415 V, and 11.9 kA at 690 V — enough for high-fault utility feeds or transformer secondaries without cascading upstream breakers. Rated insulation voltage is 800 V, so it can sit in 690 V panels with margin.
Panel fit and mounting
Width is 76.2 mm (roughly 3 inches), depth 70 mm, height 130 mm. The IP40 front protection means it's fine for enclosed panel mounting where tools or fingers won't contact live parts; no washdown rating, so keep it inside the cabinet. No auxiliary contacts or undervoltage release on this variant — the only integrated accessory is the shunt trip.