The LC3D120AM7 is a TeSys D star delta starter from Schneider, built as a pre-wired assembly with three power poles, each carrying 3 NO contacts. It's rated for 12 A in AC-3 utilisation category, which means it's designed to switch three-phase induction motors during start-up — the star-delta transition limits inrush current, then the contactor set handles full-load running. The 220 V AC coil matches standard control voltages across European and Asian panel designs.
The 12 A AC-3 rating governs motor duty, not resistive loads. AC-3 covers starting and switching off squirrel-cage motors under load. Pollution degree 3 confirms it's intended for industrial atmospheres with conductive pollution, so no extra conformal coating is needed in most cabinet environments. Fire resistance to 850 °C (IEC 60695-2-1) and V1 flame retardance (UL 94) mean the plastic housing won't propagate a flame if a fault arc or external fire hits the panel — important for UL-listed assemblies and machinery CE marking.
Where this class of part is used
Star delta starters like this one are the standard way to start three-phase induction motors above about 5 kW where direct-on-line starting would cause voltage dips or mechanical shock. The pre-wired assembly saves panel-build time — you get the three contactors, the timing relay, and the interconnections in one package that clips onto a DIN rail. Typical applications include pumps, compressors, conveyors, and fans where the load doesn't require a soft starter or VFD.