It accepts stranded power conductors from 70 up to 240 mm² on the main poles, so it's sized for the heavy feeder side of a motor branch circuit — think large pumps, compressors, or conveyor drives that pull real current. The coil connection uses spring-type terminals, which speeds up wiring and holds solid under vibration.
Physical Fit and Clearance
The 3RT1065-2NP36 measures 210 mm high by 145 mm wide by 202 mm deep. For heat dissipation and arc clearance, Siemens calls for 10 mm clearance upwards and downwards, 20 mm forwards, and 10 mm at each side. That 202 mm depth means it won't fit a shallow 200 mm enclosure without checking door clearance — plan for at least 230 mm internal depth to leave room for the arc chamber and outgoing cables.
Switching Duty and Operating Rates
This contactor is rated for different switching frequencies depending on the utilization category. In AC-1 (resistive loads) it can handle up to 800 operations per hour. In AC-3 (squirrel-cage motor starting) the max is 500 operations per hour, and the AC-3e rating matches that at 500 ops/h. For AC-4 (plugging and inching) it drops to 130 ops/h. The arc time sits at 10-15 ms, and the coil pick-up and drop-out times are both in the 80-100 ms range at AC or DC. That gives you the duty-cycle boundaries for sizing — if your application needs frequent jogging, you'll want to stay within the AC-4 rate.