The Siemens 3VA1225-5EF32-0DC0 is a SENTRON molded case circuit breaker (MCCB) rated for 250 A continuous current across a 3-pole configuration, designed for line protection. Its TM240 thermal-magnetic overcurrent release handles the overload and short-circuit trip curve. The interrupting ratings climb to 187 kA at 240 V, 121 kA at 415 V, 36 kA at 440 V, and 17 kA at 690 V — so at the common 415 V distribution level it clears faults up to 121 kA without cascading upstream. The 800 V rated insulation voltage (Ui) confirms it is built for 690 V line-to-line systems with margin.
Current derating and thermal limits
The breaker carries its full 250 A rating from 40 °C through 50 °C ambient. Above that it derates: 243.3 A at 55 °C, 236.5 A at 60 °C, 229 A at 65 °C, and 223 A at 70 °C. If the panel ambient runs above 50 °C, size the load at the derated figure — not the nameplate 250 A. Operating range is -25 °C to 70 °C; storage range is -40 °C to 80 °C.
Auxiliary and undervoltage release
This variant ships with an undervoltage release (UVR) and 2 auxiliary switches (HQ type). The integrated auxiliary trip order code is 3VA9608-0BB25. No communication module, no ground-fault monitoring, no phase-failure detection — this is a straight line-protection MCCB with a UVR for coordinated drop-out on voltage loss. The latching endurance is rated at 15,000 operations.
Dimensions and panel fit
The breaker measures 105 mm wide, 158 mm high, and 70 mm deep. Front protection class is IP40 — suitable for enclosed panel mounting where no water ingress is expected. The 3-pole footprint matches standard SENTRON 3VA panel cutouts; verify gland-plate clearance for the 70 mm depth if the enclosure is shallow.