SENTRON 3VA1040-3ED36-0BC0 — 40 A MCCB with undervoltage release
The Siemens SENTRON 3VA1040-3ED36-0BC0 is a 3-pole molded case circuit breaker rated for line protection at 40 A continuous current (Iu). It carries a TM210 thermal-magnetic overcurrent release, so the trip curve is fixed — no interchangeable trip units. The 75.6 kA breaking capacity at 240 V drops to 52.5 kA at 415 V and 32 kA at 440 V, which means you need to confirm the available fault current at your service voltage before committing the BOM line.
Thermal derating and ambient limits
The breaker holds its full 40 A rating from 40 °C up to 50 °C. Above that it derates: 38.4 A at 55 °C, 37.6 A at 60 °C, 36.8 A at 65 °C, and 36 A at 70 °C. If the panel internal ambient runs hot — say, a tightly packed enclosure next to a motor drive — size the load current against the derated figure, not the nameplate 40 A.
Integrated undervoltage release and auxiliary contacts
This variant ships with an undervoltage release (UVR) fitted — part of the auxiliary release design. That means the breaker trips if the control voltage drops below the dropout threshold, which is useful for safety interlocks or emergency-stop chains that need a hard shunt-trip response. It also carries two HQ auxiliary switches for remote status feedback. The trip indicator is not present on this version, so you won't get a local mechanical flag; the aux contacts are your only remote signal.