What this MCCB carries and where it fits
The Siemens 3VA1140-6EF36-0AB0 is a 3-pole SENTRON molded case circuit breaker (MCCB) with a TM240 thermal-magnetic overcurrent release, rated 40 A continuous at 40 °C and derating to 37 A at 70 °C ambient. Its interrupting capacity hits 220 kA at 240 V AC and still holds 154 kA at 415 V — numbers that tell you this is a high-interrupting (HI) variant meant for high-fault panels where a standard MCCB would weld open. The 800 V rated insulation voltage and 10.8 W max power loss are what you check against the switchgear temperature rise budget.
Interrupting capacity — what those numbers mean for panel coordination
At 240 V the 220 kA rating puts this breaker in the same fault-current class as large-frame power breakers, so it can sit near the transformer secondary without needing a current-limiting fuse upstream. At 415 V it still interrupts 154 kA, and at 440 V it manages 121 kA. The drop to 17 kA at 500 V and 690 V is typical for a 40 A frame — above 480 V the arc extinction physics changes, so verify your system voltage against that knee. For a 480 V delta service the 17 kA is still adequate for most distribution panels, but if your available fault current exceeds that you need the higher-voltage-rated variant.
Thermal derating and the TM240 release
The TM240 release is a fixed thermal-magnetic trip — no interchangeable rating plugs, so the 40 A is baked in. The breaker holds 40 A flat from 40 °C through 50 °C (–), then drops to 39 A at 55–60 °C, 38 A at 65 °C, and 37 A at 70 °C. That derating curve is what you apply when the breaker lives in a hot enclosure next to other heat sources. The magnetic instantaneous trip on the TM240 is factory-set and not field-adjustable, so coordination studies need the fixed curve from the Siemens selectivity data.
Physical fit and auxiliary switch configuration
Footprint is 130 mm high, 76.2 mm wide, and 70 mm deep — the 3VA1 frame size. It ships with two factory-installed auxiliary switches (HP design,), so you get status feedback without adding a separate accessory module. No undervoltage release, no ground-fault monitoring, no communication module — this is a bare line-protection breaker. If your BOM calls for shunt trip or UVR, those are field-addable accessories on the 3VA platform, but this order code doesn't include them.