Breaking capacity and current rating
The 3VM1225-5EE46-0AA2 is a 4-pole SENTRON molded case circuit breaker rated for 250 A continuous current, with a TM220 thermal-magnetic release providing LI (long-time and instantaneous) protection. The breaking capacity reaches 187 kA at 240 V AC, 121 kA at 415 V, 76 kA at 440 V, and 30 kA at 500 V — these numbers govern the fault-clearing capability at the point of installation. At 500 V the breaker still clears 30 kA, which covers most industrial distribution panels without needing an upstream current-limiting fuse.
Thermal derating and operating range
Rated current holds at 250 A from 40 °C up to 50 °C, then derates linearly: 243.3 A at 55 °C, 236.5 A at 60 °C, 229.8 A at 65 °C, and 223 A at 70 °C. The operating ambient range is -25 °C to 70 °C; storage from -40 °C to 80 °C. Maximum power loss is 57 W. Front-side protection is IP40, meaning tools or fingers won't contact live parts during normal panel access.