The Siemens SENTRON 3VA1112-3EF36-0DA0 is a 3-pole molded case circuit breaker (MCCB) rated 125 A at 40 °C, built for line protection in distribution panels. It carries a TM240 thermal-magnetic overcurrent release and an integrated undervoltage release (UVR) — that UVR trips the breaker if control voltage drops, so it's a fit for safety circuits or emergency-stop chains where you need loss-of-voltage protection built into the breaker itself.
Ratings and what they mean on the panel
The 125 A rating holds flat from 40 °C to 50 °C, then derates to 114 A at 70 °C — that's a solid thermal curve for a crowded enclosure. Interrupting capacity hits 75.6 kA at 240 V, 52.5 kA at 415 V, and 11.9 kA at 690 V. The 800 V rated insulation voltage (Ui) means it's rated for 690 V line-to-line systems without derating the dielectric. Power loss maxes at 30.6 W, so factor that into enclosure heat calculations.
Panel fit and integration
Dimensions are 130 mm high, 76.2 mm wide, 70 mm deep — standard 3-pole MCCB footprint for a SENTRON panel. No communication module, no ground-fault monitoring version on this variant; it's a straight line-protection breaker with undervoltage release. The UVR is the design-of-auxiliary-release type, so verify your control circuit voltage matches the release coil rating before wiring.