The Siemens 3RT5046-1AG20 is a SIRIUS S3 power contactor with screw-type terminals for the main current circuit, sized for motor loads up to 38 kW at 230 V or 66 kW at 400 V (at 60 °C ambient). It carries a rated insulation voltage of 1,000 V and an AC-3e maximum operating voltage of 1,000 V, so it handles 400 V and 690 V industrial networks without derating the insulation. The S3 frame is the mid-range size in the SIRIUS contactor family — wide enough for the power terminals to accept 2x 16 mm² solid/stranded or 2x 1/0 AWG, but still compact enough for a 70 mm DIN-rail footprint.
Side-by-side mounting is supported — no gap required between contactors on the rail, which saves panel width when grouping multiple motor starters.
Switching performance and thermal limits
Rated for 5,000 operating cycles per hour at AC, with a maximum of 900/h in AC-1 duty, 850/h in AC-3 and AC-3e, and 250/h in AC-4.
Auxiliary contact ratings and coil data
Auxiliary contacts are rated 6 A at 24 V, 6 A at 230 V, 3 A at 400 V, and 1 A at 110 V (50/60 Hz). The 220 V rating drops to 0.3 A. These values govern what the aux contacts can switch in control circuits — a 24 VDC PLC output driving the contactor coil, for example, sees a 6 A make/break capability, which is generous for a standard relay interface. The coil draws 0.29 A at both 50 Hz and 60 Hz at 110 V rated value.