What this MCCB is and what it does
The Siemens SENTRON 3VA1050-3ED32-0JC0 is a 3-pole molded case circuit breaker (MCCB) designed for line protection in industrial and commercial distribution panels. Rated 50 A continuously at 40 °C (derates to 45 A at 70 °C), it handles the full load current of a feeder or branch circuit without nuisance tripping up to that ambient. The 75.6 kA interrupting rating at 240 V means it can safely clear a bolted fault at that level without upstream devices needing to coordinate — a key spec for high-fault panels. At 415 V it still breaks 52.5 kA, and at 690 V it holds 7.5 kA, so it fits both 400 V and 690 V systems with adequate SCCR headroom.
Fit and integration — panel space and mounting
The breaker measures 70 mm deep by 76.2 mm wide by 130 mm high, a standard SENTRON 3VA frame size that drops into a DIN-rail or panel-mount cutout without custom bracketry. The 76.2 mm width (3 inches) matches the typical 3-pole MCCB footprint, so it fits existing busbar or cable-connection layouts. Depth of 70 mm leaves clearance for rear-mounted accessories and wiring — check gland-plate depth if the panel is shallow.
Accessories and auxiliary functions
This variant ships with a shunt trip (STL) release and two auxiliary switches (HQ type) factory-installed. The shunt trip allows remote tripping via a control signal — useful for emergency-stop circuits or PLC-driven load shedding. The two auxiliary switches provide status feedback (open/closed) to a controller or indicator lamp. No undervoltage release or ground-fault monitoring is included; those are separate order-code options. Rated insulation voltage is 800 V, and maximum power loss is 14.6 W at rated current — factor that into enclosure thermal calculations.