What the ratings mean for fit
The Siemens SENTRON 3VA1120-6GE42-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated 20 A continuous with a TM220 thermal-magnetic overcurrent release. The 220 kA breaking capacity at 240 V means it can safely interrupt fault currents up to that level without cascading upstream — critical for high-fault installations like transformer secondaries or large motor control centers. At 415 V the interrupting rating drops to 154 kA, and at 690 V to 17 kA, so the SCCR coordination study must match the available fault current at the point of installation. Current rating holds at 20 A from 40 °C through 55 °C ambient, then derates to 19 A at 60–70 °C. The 800 V rated insulation voltage (Ui) covers most 480/277 V and 600 V systems with margin. Power loss is 12 W maximum — relevant for thermal budget in a sealed enclosure.
Deployment context
Designed for line protection in distribution panels. The 4-pole configuration suits three-phase systems with a switched neutral. Dimensions are 130 mm high, 101.6 mm wide, 70 mm deep — the width of a standard 4-pole MCCB footprint. Verify busbar and mounting hole pattern against the existing panel layout; the depth leaves clearance for rear-connected cables.