The Siemens SENTRON 3VA1112-3GE42-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated 125 A at 40 °C, with a TM220 thermal-magnetic release for line protection. Its interrupting capacity reaches 75.6 kA at 240 V AC and 52.5 kA at 415 V AC, making it suited for high-fault panels where selectivity and SCCR headroom matter.
The 125 A rating holds flat from 40 °C to 50 °C, then derates to 114 A at 70 °C — useful when the breaker sits in a warm enclosure near other heat sources. The 75.6 kA at 240 V AC and 52.5 kA at 415 V AC tell you the breaker can safely interrupt fault currents up to those levels without upstream coordination failure. The TM220 release is a thermal-magnetic design — thermal element handles overloads, magnetic element handles short-circuits. Power loss is 28.1 W maximum, which matters for enclosure thermal budgeting.
At 70 mm deep, 101.6 mm wide, and 130 mm tall, the 3VA1112-3GE42-0AA0 fits standard DIN-rail or panel-mount layouts. The 4-pole design handles three-phase plus neutral (100 % N-conductor protection).