What this SIRIUS S6 soft starter does
At 50 °C it's rated 145 A; at 60 °C it's 125 A. That derating curve means you size the starter for the enclosure temperature, not the motor nameplate — out here in the grease, a hot panel can cost you 20 A of headroom. Minimum load is 20 % of rated current.
It's a screw-fixing unit — no DIN-rail snap-on here. The main current circuit uses busbar connection, and the terminal acceptance is generous: solid 2x (0.5 to 2.5 mm²) for aux contacts, stranded 2x (25 to 120 mm²) for power, and finely stranded 2x (16 to 95 mm²). For the main contacts, it accepts 4 to 250 kcmil. Dimensions are 198 mm high, 120 mm wide, 250 mm deep. Clearance requirements: 100 mm upwards, 75 mm downwards, 5 mm at the sides. That side clearance is tight — you can stack these close together on a backplate, but the vertical airflow needs room.