S3 frame power contactor for motor and resistive loads
The Siemens SIRIUS 3RT1446-6AV66-ZM95 is a size S3 power contactor rated 22 kW at AC-2 duty on 400 V — the category for slip-ring motor starting and moderate overloads. It also carries 29.9 kW at AC-3 at 500 V and 38.2 kW at 690 V, covering a wide motor range without stepping up frame size. Insulation voltage is rated 1 000 V, with pollution degree 3, so it's comfortable in industrial panels where dust and conductive deposits are a given. The 90 mm width and 146 mm height fit the standard S3 footprint; depth is 139 mm — measure your gland plate clearance before sliding it in. Main circuit terminals are screw-type, accepting AWG 7 to 1/0, with solid cross-sections from 2x 0.5 mm² up to max 2x 4 mm² per clamp. No special crimp tool needed — field-replaceable with standard screwdrivers.
Mounting and integration
Fastens with screws or snaps onto 35 mm and 75 mm standard DIN rails — no adapter plate required. Side-by-side mounting is allowed, so you can gang contactors in a motor control centre without dead spaces. Operating temperature range is -25 to +60 °C; storage from -55 to +80 °C. That -25 °C low end matters if the panel sits in an unheated warehouse or outdoor enclosure in winter.
Coil and auxiliary ratings
Coil draws 10 A at 24 V DC, with a dropout time of 14 to 20 ms — fast enough to clear a fault before downstream contacts weld. On the AC side, arcing time runs 10 to 15 ms. Mechanical life is typical 10 000 000 operations; no contactor lasts forever, but this one will outlast most of the machines it starts. Auxiliary contact ratings cover the common control voltages: 2 A at 60 V DC, 1 A at 110 V, 0.3 A at 220 V, and 6 A at 230 V AC. Enough for pilot duty and PLC input isolation.
Lifecycle and compliance
Substance prohibition date is 05/01/2012, which aligns with the original RoHS compliance deadline. The contactor is IP00 on the front and at the terminals — open-style, intended for enclosures, not standalone outdoor use.