The Siemens 3RT2016-1HA42 is a SIRIUS 3RT power contactor rated for AC-3e/AC-3 duty at 9 A, switching motor loads up to 4 kW at 400 V. That AC-3e rating means it's tested for switching three-phase induction motors — the kind driving pumps, fans, and conveyors out here in the grease — and can handle the inrush without welding contacts. The 12 V DC coil pulls in reliably across 0.7–1.25× Uc, so it'll hold on a nominal 12 V supply even if the battery or control transformer sags under load.
Panel fit and wiring constraints
One NC auxiliary contact is built in, and no additional auxiliary switch block can be added to this variant — if you need more feedback contacts, pick a different order code within the S00 frame.