The Siemens SENTRON 3VA2040-7HM36-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, carrying a continuous current Iu of 40 A across the entire ambient temperature range from 40 °C to 70 °C — no derating needed up to that ceiling. Breaking capacity hits 330 kA at 240 V (242 kA at 415 V, 187 kA at 500 V, and 3 kA at 690 V), which means it can interrupt fault currents at the high end of the available short-circuit spectrum without cascading upstream — relevant for transformer-secondaries or high-capacity bus risers.
Release and integration
The overcurrent release is an ETU330 electronic trip unit, adjustable response time tr from 0.5 s to 17 s, giving the commissioning engineer room to coordinate with downstream devices without sacrificing selectivity.