The Siemens 3VA1110-4GF42-0AA0-ZD00 is a 4-pole IEC frame 160 circuit breaker from the 3VA1 series, rated at 100 A with a breaking capacity class S delivering Icu=36kA at 415 V. This puts it in the sweet spot for main or feeder protection in industrial panels where fault currents are substantial but not extreme — think distribution boards feeding motor control centers or lighting sub-panels in a plant.
What the ratings mean for fit
The 36 kA breaking capacity at 415 V (Icu) tells you this breaker can safely interrupt a fault up to that level without welding its contacts or failing catastrophically. That's an SCCR (short-circuit current rating) anchor for the panel label — if your available fault current at the board is 30 kA, this breaker has headroom. The TM240 thermal-magnetic trip unit gives you adjustable overload protection (Ir) from 70 A to 100 A, so you dial it to match the cable or load, not the other way around. Short-circuit pickup (Ii) is fixed at 5 to 10 times In (500–1000 A), which is standard for distribution — it'll ride through motor inrush but clear a bolted fault fast. The 'N conductor protection 100%' means the neutral pole is fully rated and trips with the phases — no derating needed for 4-wire systems with harmonic content. The nut keeper kit is a mechanical detail for DC Power OEM builds in China; it keeps the terminal nuts captive during assembly, which saves a headache on a line where dropped hardware stops the build.
Where it fits in the panel
The 3VA1 frame mounts on a DIN rail or can be screw-fixed to a backplate in a standard IP54 or IP65 enclosure. Four-pole at 100 A means it takes up a 4-module width on the rail — plan your gland plate and busbar takeoff accordingly. The TM240 trip unit is field-adjustable, so you can set Ir without pulling the breaker out of the panel, which matters when you're commissioning a line and the load calc came in at 85 A instead of the spec'd 100 A.