The Siemens SENTRON 3VA1125-5EE32-0JF0 is a 3-pole molded case circuit breaker rated 25 A at 40 °C, with a breaking capacity of 187 kA at 240 V AC — that means it can safely interrupt a fault current of 187 kA at that voltage, which is high enough for most industrial main-feed applications where the available fault current is substantial. The breaker carries a shunt trip (STL) and an auxiliary switch configuration of 1 auxiliary switch + 1 trip alarm switch HQ, which gives remote status indication and a remote trip capability — useful for emergency-off circuits or remote shutdown interlocks. Rated insulation voltage is 800 V, and the unit is rated for operation from -25 °C to 70 °C, with storage from -40 °C to 80 °C. The maximum power loss is 8.5 W.
The breaking capacity drops as voltage rises: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at both 500 V and 690 V.
Current derating with temperature
The breaker is rated 25 A continuously at ambient up to 50 °C. At 55 °C and 60 °C it derates to 24 A, and at 65 °C and 70 °C to 23 A. That is a mild derating curve — you lose only 2 A over a 30 °C rise, so it runs cool in a warm enclosure.
The breaker measures 70 mm deep, 76.2 mm wide, and 130 mm high — a standard 3-pole MCCB footprint for a 25 A frame.