The Siemens 3VA1225-5GE42-0AA0-ZD00 is a 4-pole IEC frame 250 molded case circuit breaker with a 55 kA interrupting capacity at 415 VAC (breaking capacity class M). It carries a TM220 thermal-magnetic trip unit rated at 250 A continuous, with adjustable overload protection (Ir) from 175 A to 250 A and fixed short-circuit protection (Ii) set at 10 times In. The N conductor is protected at 100%, and the unit includes a nut keeper kit specified for DC Power OEM applications in China. This is a current-production part, sourced to order against an RFQ through independent distribution.
What the ratings mean for fit
The 55 kA Icu at 415 V means this breaker safely interrupts faults up to that level without upstream cascading — critical for high-fault-capacity panels where a lower-rated breaker would require a current-limiting fuse or larger upstream device. The TM220 thermal-magnetic trip provides fixed magnetic pickup at 10x In (2500 A), so it's sized for motor or transformer branch circuits where inrush won't nuisance-trip the instantaneous element. The adjustable Ir band (175–250 A) lets you dial in the cable or load rating without changing the breaker body. The 4-pole configuration with 100% N protection is required on 3-phase + N systems where the neutral carries harmonic or unbalanced current — common in data center or VFD-fed panel feeds.
