What it is and what it does
The Siemens SENTRON 3VA2110-7MN32-0DC0 is a 3-pole molded case circuit breaker (MCCB) in the motor protection version, rated for a continuous current Iu of 100 A and an insulation voltage Ui of 800 V. It uses an ETU350M electronic overcurrent release, which gives you adjustable thermal and magnetic protection curves for motor loads — not just a fixed thermal bimetal. The unit includes phase failure detection, so it will trip on a lost phase before the motor single-phases and burns up. Breaking capacity is the headline: 330 kA at 240 V, 242 kA at 415 V and 440 V, 187 kA at 500 V, and 52.5 kA at 690 V. That means it can safely interrupt a fault up to those levels without welding contacts or venting gas into the panel. For a 100 A frame, that is a very high interrupting rating — it is sized for installations with high available fault current, like large industrial switchboards or transformer secondaries.
Thermal derating and panel fit
The breaker carries its full 100 A rating from 40 °C through 50 °C ambient. Above that, it derates: 96 A at 55 °C, 94 A at 60 °C, 92 A at 65 °C, and 90 A at 70 °C. If your panel internal ambient runs hot, you need to account for that in the load schedule — the breaker will trip earlier than a 100 A nameplate suggests. Maximum power loss is 75 W, which matters for ventilation in a sealed enclosure. Physical dimensions: 105 mm wide, 181 mm tall, 86 mm deep. That is a standard 3-pole MCCB footprint for the 100 A frame class — it fits in most panel-mounted or DIN-rail adapter arrangements. The auxiliary contact configuration is 2 auxiliary switches HQ, and the integrated auxiliary trip is order code 3VA9608-0BB25. The supplied basic switch is 3VA2110-7MN32-0AA0.