The Siemens SENTRON 3VA1140-3EF36-0DA0 is a 3-pole molded case circuit breaker (MCCB) rated 40 A at 40 °C, with a TM240 thermal-magnetic overcurrent release. It carries a breaking capacity of 75.6 kA at 240 V AC, derating to 52.5 kA at 415 V and 11.9 kA at 690 V.
This MCCB's interrupting rating is voltage-dependent: 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 11.9 kA at both 500 V and 690 V.
Above that, derating is gradual: 39 A at 55 °C and 60 °C, 38 A at 65 °C, 37 A at 70 °C. In a hot mill environment near the rolls, the 70 °C ceiling means the breaker can sit inside a ventilated enclosure without forced cooling — it takes the radiant heat.
Undervoltage release and auxiliary options
No communication function, no ground-fault module, no trip indicator. The design is line protection, not motor protection; the TM240 thermal-magnetic release handles overload and short-circuit within the same package.
Footprint: 76.2 mm wide (3 in), 130 mm tall (5.12 in), 70 mm deep (2.76 in). Max power loss at rated load is 13.3 W — modest heat rejection for a 40 A frame, but account for it in a sealed cabinet with other breakers.