SENTRON 3VA1112-5EF32-0AH0 — 125 A MCCB with TM240 Release
The Siemens 3VA1112-5EF32-0AH0 is a SENTRON molded case circuit breaker (MCCB) in a 3-pole, line-protection design. It carries a 125 A continuous rating at 40 °C, with a TM240 thermal-magnetic overcurrent release — meaning the thermal element tracks load heating for overloads, and the magnetic element trips instantaneously on short-circuit currents above the release setting. The 187 kA breaking capacity at 240 V gives it headroom for high-fault panels, and the 800 V rated insulation voltage suits it for 480 V and 600 V class systems.
Key Ratings and What They Mean for the Panel
Rated 125 A continuously at 40 °C, derating to 114 A at 70 °C — the thermal curve governs real-world loading in a warm enclosure. The TM240 release is a fixed thermal-magnetic type; no interchangeable trip unit, so the 125 A frame is sized to the load, not adjustable downward. Breaking capacity steps from 187 kA at 240 V down to 17 kA at 690 V, so the SCCR coordination study must use the voltage at the fault point. Power loss of 28.1 W maximum factors into enclosure thermal calculations.
Panel Integration and Footprint
Mounts on DIN rail with a 76.2 mm (3 in) width — three 18 mm pole spaces — and a 70 mm (2.76 in) depth. The 130 mm (5.12 in) height fits standard distribution panelboards. The auxiliary switch configuration (2 auxiliary switches + 1 trip alarm switch HQ) is built in, so no add-on modules are needed for status feedback or remote tripping indication.