Key ratings and what they mean for fit
The 3VA1225-4EF32-0AA0-ZD00 is a 3-pole IEC molded-case circuit breaker from the Siemens 3VA1 series, rated at 250 A continuous current with a breaking capacity of 36 kA at 415 V AC (class S). That 36 kA Icu means it can safely interrupt a fault current up to that level without welding contacts or cascading upstream — critical for selectivity studies in distribution panels where downstream faults must be cleared locally. The thermal-magnetic trip unit (TM240) gives you adjustable overload protection (Ir from 175 A to 250 A) and fixed short-circuit pickup (Ii 5 to 10 times In, so 1250 A to 2500 A). This breaker is sized for line protection in OEM DC power equipment built in China, per the special nut keeper kit variant.