What It Is — and What the Ratings Mean for Fit
The Siemens 3RT2017-2LF42-1LA0 is a SIRIUS power contactor in the compact Size S00 frame (45 mm wide, 70 mm tall, 121 mm deep). It is designed for switching motor loads in control panels and industrial machinery, with a 110 VDC coil and spring-type terminals that accept 0.5 to 4 mm² solid or stranded wire. The DC coil holds at 110 V nominal; the rated control supply voltage is DC, so verify your control circuit provides clean DC before committing this part to the BOM. The spring-type terminals (push-in or cage-clamp style) reduce wiring time compared to screw terminals and stay secure under vibration — a real advantage on a conveyor line or compressor skid. Contact ratings span the full AC-3 motor switching curve: 11 A at 480 V and 11 A at 600 V, making it suitable for 3 hp at 230 V and for motor loads up to roughly 5.5 kW at 400 V. The DC switching ratings are lower — 10 A at 24 V, 1 A at 110 V, 0.3 A at 220 V — so if this contactor feeds a DC load, derate accordingly.
Mounting and Integration — Panel Fit
Mounts via screw and snap-on onto 35 mm DIN rail per DIN EN 60715. The Size S00 footprint (45 mm wide) is the smallest Siemens contactor frame, so it fits tightly spaced rail assemblies. Allow 10 mm clearance upwards and forwards, 10 mm downwards, and 6 mm at the sides for arc dissipation and cooling. Operating temperature range is -40 to +70 °C; storage range -55 to +80 °C. That covers most indoor panel environments, including unheated warehouse or rooftop installations in temperate climates.