What this 3VA1 breaker does on the line
The Siemens 3VA1220-6GF42-0AA0-ZD00 is a 4-pole IEC frame 250 molded-case circuit breaker rated for 200 A continuous current, with a 70 kA interrupting capacity at 415 V (breaking capacity class H). The TM240 thermal-magnetic trip unit provides adjustable overload protection (Ir = 140 A to 200 A) and fixed short-circuit protection (Ii = 5 to 10 × In, so 1000 to 2000 A). The 100% N-conductor protection means the neutral pole is fully rated, not just a switched neutral — necessary for 4-wire systems with harmonic content where neutral current can approach phase current. This variant includes a nut keeper kit and is configured for DC Power OEM applications in China. The nut keeper secures the line/load lug fasteners against vibration in transport or high-vibration environments like inverter cabinets.