The Siemens SENTRON 3VA2140-7KQ36-0AA0 is a 3-pole molded case circuit breaker rated for 40 A continuous current, designed for line protection in distribution panels. Its 330 kA breaking capacity at 240 V gives it headroom for high-fault utility feeds or transformer secondaries — the sort of installation where a standard MCCB would run out of interrupting rating on the first phase-to-phase bolted fault. The 40 A rating holds flat from 40 °C up to 70 °C, so no derating curve to chase in a warm enclosure.
Breaking capacity and selectivity
At 415 V the interrupting rating is 242 kA, and at 500 V it still holds 187 kA — only at 690 V does it drop to 3.7 kA, which is typical for a 40 A frame at that voltage. That means this breaker coordinates well upstream of a 25 kA panelboard main; you get full selectivity without oversizing the feeder breaker. The insulation voltage is rated 800 V, so the 690 V rating is within the design envelope.
Mounting and integration
The 3VA2140-7KQ36-0AA0 measures 105 mm wide, 181 mm tall, and 86 mm deep — fits standard Siemens 3VA panel cutouts and busbar risers. It includes a communication function for remote monitoring and a ground-fault monitoring version using summation current formation on the L-conductor. No undervoltage release, no trip indicator; the trip unit is set to a full-scale value of 40 A with an initial value of 16 A.