What this 3VA1 MCCB carries
The Siemens 3VA1220-5EF42-0AA0-ZD00 is a 4-pole IEC frame 250 molded case circuit breaker with a 55 kA breaking capacity at 415 V (class M). That interrupting rating means it can safely clear a fault up to 55 kA without welding its contacts or rupturing the arc chamber — critical for panel coordination studies where the available fault current at the line side is known to be high. It ships with a TM240 thermal-magnetic trip unit rated In=200 A, with adjustable overload protection (Ir) from 140 A to 200 A and short-circuit protection (Ii) set at 5 to 10 times In. The thermal element handles sustained overloads; the magnetic element clears bolted faults instantly. That Ir range lets you dial in the breaker for a specific downstream load without swapping the trip unit. The N conductor is unprotected on this variant — the neutral pole does not have an overcurrent trip element. That is standard for line-side protection where the neutral is bonded upstream; it is not a general-purpose feeder breaker for a 4-wire system with downstream neutral loads. Verify the system grounding scheme before specifying.
Panel integration notes
This is a 4-pole IEC frame 250 breaker — it occupies the same DIN-rail or screw-mount footprint as other 3VA1 frame 250 units. The nut keeper kit (part of the -ZD00 spec) retains the terminal nuts during wiring, which saves time on a panel assembly line. The unprotected N pole means the neutral bus bar connects directly through without a trip element; plan the neutral bar routing accordingly.