The Siemens SENTRON 3VA1140-4EF36-0AB0 is a 3-pole molded case circuit breaker (MCCB) rated for 40 A continuous current at 40 °C, designed for line protection in distribution panels and switchgear assemblies. Its interrupting capacity hits 121 kA at 240 VAC and 75.6 kA at 415 VAC — figures that place it squarely in high-fault-current applications like mains incoming feeders or large motor control center (MCC) bus ties.
Breaking capacity and selectivity
At 415 VAC the breaker clears 75.6 kA; at 440 VAC it still manages 52.5 kA. That gives the panel designer headroom for selective coordination with downstream 10 kA or 25 kA branch devices — the upstream MCCB can let a fault ride through long enough for the closest device to open, keeping the rest of the bus live. The rated insulation voltage of 800 V confirms it is built for 690 VAC systems common in industrial plants.
Thermal-magnetic release and derating
The overcurrent release is a TM240 — thermal-magnetic, fixed thermal pickup at 40 A, magnetic short-circuit trip set at 240 A (6× In). The breaker holds full 40 A through 50 °C ambient; at 55 °C it derates to 39 A, at 65 °C to 38 A, and at 70 °C to 37 A. That matters when the MCCB is packed into a high-density panel with other heat sources. Maximum power loss at rated load is 10.8 W.
Physical fit and auxiliary contacts
Footprint is 76.2 mm wide, 130 mm tall, 70 mm deep — standard 3-pole MCCB width for a 40 A frame. It ships with two factory-installed auxiliary switches (HP type) for status feedback to a PLC or indication lamp. No undervoltage release, no shunt trip, no ground-fault module on this variant; those are add-on accessories in the 3VA platform.