What this MCCB covers
The Siemens 3VA1040-3ED36-0KA0 is a SENTRON molded case circuit breaker for line protection — 3-pole, rated 40 A at 40 °C, with a TM210 thermal-magnetic release and an integrated shunt trip (STL) for remote tripping. It's a panel-mount unit sized at 70 mm deep, 76.2 mm wide, and 130 mm tall, so it fits standard MCCB slots in a distribution board without needing extra gland-plate work.
Breaking capacity and what it means on site
This breaker's interrupting ratings are given per voltage level — 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 7.5 kA at both 500 V and 690 V. That spread matters because the same unit on a 415 V line handles a 52.5 kA fault, but on a 690 V circuit it's limited to 7.5 kA. If you're swapping one into an existing panel, check the available fault current at your system voltage — don't assume the 75.6 kA figure holds across all taps.
Thermal derating and continuous current
Rated 40 A from 40 °C up to 50 °C, then it starts to taper: 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 this breaker lives in a hot enclosure — say next to a drive or a transformer — you lose about 4 A by the time you hit 70 °C ambient. Plan your load accordingly; the nameplate 40 A is only good if the panel stays under 50 °C.
Shunt trip and auxiliary release
This unit carries a shunt trip (STL) auxiliary release — that's the coil that lets you trip the breaker remotely from a pushbutton or a safety relay. No undervoltage release fitted, no ground-fault monitoring. The TM210 overcurrent release handles the thermal-magnetic protection; the shunt trip is a separate add-on for emergency-off or interlock circuits. Power loss at full load is 10.8 W, so factor that into your enclosure heat budget.