Unlike a molded-case circuit breaker, this unit provides no overload or short-circuit protection — it's a straight disconnect for isolating loads under load or no-load conditions, per its designation as an SD100 (switch disconnector 100 A frame).
Front terminal connection for the main circuit — clamp-type, sized for the 125 A path. The 76.2 mm width (3 inches) and 70 mm depth match the standard 3VA1 IEC frame 160 footprint, so it drops into a panel cutout or DIN-rail assembly already laid out for that family. Two built-in CO auxiliary contacts (HP design) give you feedback on the disconnect position without bolting on an external switch block.
What it is not
The closest functional peer in the 3VA1 family is the 3VA1112-5EE32-0AA0 — a full molded-case circuit breaker with TM220 thermal-magnetic trip and LI protection characteristic, rated 125 A at 40 °C but with a 20 000-cycle mechanical life versus this disconnect's 15 000 cycles. The breaker also carries a 28.1 W power loss at max load versus this disconnect's 38 W. If your BOM calls for a disconnect-only device, the 3VA1112-1AA36-0AB0 is the correct part; the breaker variant adds protection functions that may not be wanted in a circuit already protected upstream.