What this 110 V DC coil contactor fits
The 3RT2046-3XF44-0LA2: This is a Siemens SIRIUS Size S3 contactor with a 110 V DC coil — not the common 24 V DC or 230 V AC version. The DC coil draws a 1.5 A inrush peak at the 110 V rated value, so the control transformer or DC supply needs to handle that surge without dropping below the pick-up voltage. The spring-type terminals on the magnet coil save a screwdriver turn per wire — useful when you're wiring a dozen of these in a row. Mechanical life is 10 million operations typical, and the AC-4 switching rate maxes at 250 operations per hour — that's the heavy-duty jogging/reversing ceiling. For a conveyor or hoist application cycling faster than that, you'd need to step up to a larger frame or add a soft starter to reduce arcing stress.
Mounting and panel fit — DIN rail plus screws
Fastening method is screw and snap-on onto 35 mm standard mounting rail per DIN EN 60715. The dual option means you can screw it to a backplate in high-vibration spots where the DIN rail clip alone might rattle loose, or snap it on for quick assembly in a standard panel. Mounting position allows +/-180° rotation on a vertical surface and +/-22.5° tilt forward and backward — handy when the enclosure forces an odd angle. Clearance distances are 10 mm upwards, 10 mm downwards, 10 mm at the side, and 20 mm forwards. Those are the minimum air gaps for arc flash containment and heat dissipation — pack them tighter and the contactor's switching life drops. The dimensions are 200 mm depth, 70 mm width, 140 mm height, so it fits a standard 200 mm deep enclosure with room for wiring ducts.
Lifecycle and sourcing — active, no obsolescence worry
Operating temperature range is -40 to +70 °C, storage range -55 to +80 °C. That covers unheated outdoor cabinets in cold climates and warm panels near ovens. The DC operating time is 38 to 57 ms — slower than an AC coil but consistent, so factor it into your sequence timing if this contactor is in a safety circuit or a staged start-up.