The Siemens 3VA1225-6GE42-0AA0-ZD00 is a 4-pole IEC frame 250 molded case circuit breaker with a 70 kA interrupting capacity at 415 V (breaking capacity class H). It carries a TM220 thermal-magnetic trip unit — the thermal element adjustable from 175 A to 250 A, the magnetic fixed at 10× In. That 70 kA rating means it can safely clear a bolted fault on a 415 V secondary without upstream fuses needing to coordinate; in a typical distribution panel, it's the main or a large feeder breaker sized for a 250 A bus.
What the Ratings Mean for Fit
The 70 kA Icu at 415 V puts this in breaking capacity class H — the highest standard class for the 3VA1 frame. That matters for high-fault installations like industrial substations or large motor control centers where the available fault current exceeds 50 kA. The TM220 trip unit gives you thermal adjustment from 175 A to 250 A (the Ir range), so you can fine-tune overload protection to the actual continuous load without swapping the breaker body. Magnetic pickup at 10× In (2500 A) is fixed — that's a standard motor-start or cable-protection curve, not a selective or generator-protection characteristic.
Integration Notes
This is a 4-pole breaker with 100% N-conductor protection — the neutral pole is switched and protected, not just a solid link. That makes it suitable for TN-S or TT systems where the neutral must be disconnected and protected. The nut keeper kit (part of the ZD00 suffix) is factory-fitted for DC Power OEM builds in China; it retains the terminal nuts during panel wiring. Mounts in a standard IEC distribution board or enclosure on a mounting plate — no DIN rail adapter for this frame size.