Siemens SENTRON 3VA1225-4GF42-0CA0 is a 4-pole molded case circuit breaker (MCCB) rated 250 A continuous current, with a TM240 thermal-magnetic release. It carries 121 kA interrupting capacity at 240 V, 75.6 kA at 415 V, 25 kA at 440 V, and 11.9 kA at 690 V — the 240 V figure is the one that governs most North American panel schedules, while the 415 V rating is the one for 400 V-class European distribution. An undervoltage release is integrated; no auxiliary contacts, no communication module, no ground-fault monitoring.
Ratings and what they mean for fit
The 250 A rating holds flat from 40 °C through 50 °C ambient — no derating needed in a standard 40 °C panel. Above 50 °C it drops linearly to 223 A at 70 °C. That matters if the breaker sits near a heat source or in a non-ventilated enclosure; at 55 °C you still have 243.3 A, so a 250 A feeder is still viable in a warm cabinet. Rated insulation voltage is 800 V, which covers 690 V systems with margin. The TM240 release is a fixed thermal-magnetic type — no interchangeable trip unit, so the breaker is dedicated to its 250 A setting. N-conductor protection is 100% rated, meaning the fourth pole handles full current, not a reduced neutral. Front protection is IP40 — finger-safe from the front but not sealed against dust ingress. No auxiliary contact version is fitted; if you need status feedback, the integrated undervoltage release (UVR) can be wired into a control circuit, or you add the optional auxiliary trip accessory 3VA9608-0BB24.
Where it lands in the panel
Footprint is 140 mm wide by 158 mm tall by 70 mm deep — a 4-pole frame that fits standard MCCB panel cutouts. Depth at 70 mm is shallow enough for most 200 mm-deep enclosures without crowding the gland plate. Operating temperature range is -25 °C to 70 °C; storage from -40 °C to 80 °C. Latching endurance is 15,000 operations — not a switching breaker for frequent load making/breaking, but fine for infrequent manual isolation and fault clearing. No voltage trigger or phase failure detection is built in; the UVR handles undervoltage only.