The Siemens 3VA1120-6GE42-0AA0-ZD00 is a 4-pole IEC frame 160 molded case circuit breaker with a 70 kA breaking capacity at 415 V (class H). It's configured for line protection with a TM220 thermal-magnetic trip unit set at In=20 A, overload protection adjustable Ir=14 A...20 A, and fixed short-circuit protection Ii=16 x In. The N conductor is protected at 100%, and the unit includes a nut keeper kit for DC Power OEM applications in China.
What the ratings mean for fit
The 70 kA Icu at 415 V means this breaker can safely interrupt a fault current up to that level without welding its contacts or failing catastrophically — essential for high-fault-capacity installations like transformer secondaries or large motor control centers. The TM220 thermal-magnetic trip gives a fixed thermal curve with adjustable overload pickup (Ir) between 14 A and 20 A, so you tune the long-time protection to the actual load without swapping the trip unit. The 16 x In instantaneous setting (320 A) clears hard shorts fast but avoids nuisance tripping on motor inrush or capacitor charging currents.
Deployment context
The 3VA1 frame mounts into standard Siemens panelboard or switchboard bus systems. The 4-pole configuration covers three-phase plus neutral, and the 100% N protection means the neutral pole trips at the same rating as the phase poles — required for systems with significant harmonic content or non-linear loads where the neutral carries current. The nut keeper kit simplifies assembly in DC Power OEM builds where the breaker is installed into a pre-drilled enclosure.