The Siemens SENTRON 3VA2040-5KQ42-0AA0 is a 4-pole molded case circuit breaker rated at 40 A continuous current (Iu) across the full ambient range from 40 °C to 70 °C — no derating needed up to that ceiling. That flat thermal curve simplifies panel design: you don't have to oversize for a hot enclosure. Breaking capacity is the headline here: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 3 kA at 690 V. The ground-fault monitoring uses summation current formation on L+N, so it catches leakage without a separate core-balance CT. Communication function is built in, and an optional motor drive is available for remote tripping or re-closing.
Optional motor drive and communication function mean it can be integrated into a remote-controlled or monitored distribution system without a separate contactor or RTU.