The Siemens SENTRON 3VA1125-6EF32-0CA0 is a 3-pole molded case circuit breaker (MCCB) rated for 25 A continuous current, with a TM240 thermal-magnetic overcurrent release. Its breaking capacity reaches 220 kA at 240 V, 154 kA at 415 V, 121 kA at 440 V, and 17 kA at 690 V — figures that define the fault-clearing capability at the point of installation, not the running load.
Breaking capacity and thermal derating
The 220 kA at 240 V and 154 kA at 415 V ratings mean this MCCB can interrupt very high fault currents without upstream coordination failure — critical for transformer secondaries or bus-tie positions where available fault current exceeds 100 kA. The TM240 release is fixed-thermal, fixed-magnetic; no interchangeable trip units. The thermal derating curve is flat at 25 A from 40 °C through 50 °C, then drops to 24 A at 55 °C, 23.5 A at 60 °C, 23 A at 65 °C, and 22.5 A at 70 °C. If the panel ambient runs above 50 °C, the continuous current must be reduced accordingly.
Undervoltage release and auxiliary options
This variant includes an undervoltage release (UVR) as the integrated auxiliary trip — part number 3VA9608-0BB24. The UVR trips the breaker when supply voltage drops below a threshold, protecting downstream equipment from brownout conditions. No auxiliary contacts or shunt trip are fitted on this unit; those would need to be added externally if required. The latching endurance is rated at 15,000 cycles.
Physical fit and environment
Dimensions are 130 mm height, 76.2 mm width, 70 mm depth — a standard 3-pole MCCB footprint that fits most SENTRON panelboards and distribution blocks. Front protection is IP40, meaning tools and fingers are kept out, but the breaker is not sealed against water ingress. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The reference code per DIN EN 81346-2 is Q (switching device).