The Siemens SENTRON 3VA1125-3EF32-0AD0 is a 3-pole molded case circuit breaker (MCCB) rated for 25 A continuous current at 40 °C ambient, carrying that full rating up to 50 °C before the thermal derating curve begins to pull it back — at 70 °C it still holds 23 A, so it holds the unit on the grid through a hot switchroom provided the ventilation path is clear. The TM240 thermal-magnetic release gives it a fixed thermal pickup calibrated for 25 A frame; the magnetic instantaneous trip point is factory-set inside the release, not field-adjustable, so coordination studies need that fixed band confirmed against downstream device let-through. Interrupting capacity is what decides whether this breaker survives a bolted fault without welding its contacts shut: 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 — adequate for most industrial secondary-distribution panels, provided the available fault current at the breaker line terminals does not exceed those figures for the system voltage.
Lifecycle and sourcing — active line, no obsolescence concern
Power loss at full rated current is 8.5 W maximum — relevant for enclosure thermal budgeting when grouping several breakers in a single panel.
Integration — footprint and mounting constraints
The breaker measures 130 mm high, 76.2 mm wide, and 70 mm deep — a standard 3-pole MCCB footprint that fits SENTRON distribution panels and most third-party enclosure mounting plates without adapter brackets. The basic switch supplied is order code 3VA11253EF320AA0 — the bare switching mechanism without the trip unit.