The Siemens SENTRON 3VA1120-6EF36-0HA0 is a 3-pole molded case circuit breaker (MCCB) rated for 20 A continuous at 40 °C, with the TM240 thermal-magnetic overcurrent release. Its breaking capacity reaches 220 kA at 240 V, 154 kA at 415 V, and 121 kA at 440 V — figures that put it in the high-interrupting category for line protection in industrial switchgear. This MCCB includes a factory-fitted shunt trip release (STL) for remote tripping, and its rated insulation voltage is 800 V. The unit is designed for line protection, not motor protection — the TM240 release curve is thermal-magnetic, sized for feeder or distribution circuits.
Breaking capacity and selectivity
The 220 kA at 240 V and 154 kA at 415 V ratings mean this breaker can safely interrupt very high fault currents — typical for large transformer secondaries or close-coupled busway. At 690 V it still holds 17 kA, so it works in 690 V distribution without cascading upstream. For a site electrical engineer coordinating a panel, those numbers give headroom for selective coordination with downstream breakers. The 20 A rating holds steady from 40 °C up to 55 °C, then derates to 19 A at 60 °C through 70 °C. That's a tight thermal curve — no surprise derating in a warm enclosure, but worth noting if your ambient regularly exceeds 55 °C.
Physical fit and panel integration
Dimensions: 130 mm tall, 76.2 mm wide, 70 mm deep. Mounts on a DIN rail or direct panel. The 3-pole footprint is standard for a 20 A frame — no surprises when swapping into an existing SENTRON 3VA lineup. The shunt trip (STL) is built in, so no external trip module to add. No undervoltage release, no ground-fault monitoring, no communication module on this variant — it's a straight line-protection breaker with remote trip capability.