40 A MCCB with flat thermal derating to 70 °C
The Siemens SENTRON 3VA2040-8JQ46-0AA0 is a 4-pole molded case circuit breaker rated for 40 A continuous current, sized for line protection in distribution panels. It holds its full 40 A rating from 40 °C all the way up to 70 °C ambient — no derating curve to calculate in a hot enclosure. That flat thermal performance is the spec that matters when you're stacking breakers in a packed cabinet. Interrupting capacity reaches 440 kA at 240 V, 330 kA at 415 V and 440 V, 220 kA at 500 V, and 52.5 kA at 690 V — headroom for high-fault installations where a standard MCCB would weld closed. The 4-pole design covers three-phase plus neutral switching, common in North American and European distribution schemes where the neutral needs protection or isolation.
Footprint and integration
The case measures 86 mm deep, 140 mm wide, 181 mm tall. Power loss is 1.2 W maximum.
Built-in communication and ground-fault monitoring
This MCCB includes a communication function for integration into a monitored distribution system — no separate add-on module required for basic connectivity. The ground-fault monitoring uses summation current formation on L + N conductors, detecting leakage without an external GFCI relay. Trip indicator is not fitted, so fault events are signaled through the communication channel rather than a local flag.
Lifecycle and sourcing
Listed as current production — no end-of-life notice on this order code. Available to order through independent distribution; current pricing and lead time are confirmed at quote time against an RFQ.