The Siemens SIRIUS 3RW4056-2BB34 is a soft starter with thyristors. It is rated 162 A at 40 °C, 145 A at 50 °C, and 125 A at 60 °C. Control voltage is 115 V AC, 50/60 Hz. Insulation voltage is 600 V. Size S6: 120 mm wide, 198 mm high, 250 mm deep. Screw fixing. Clearance: 100 mm above, 75 mm below, 5 mm sides.
Main circuit connection is via busbar (cite:) — not a standard screw terminal. The main contact wire range covers 4 to 250 kcmil (cite:) and the clamping points accept 6 AWG to 2/0 at the front and back (cite:,), or up to 2x 1/0 using both clamping points (cite:). Control and auxiliary wiring uses solid 0.25 to 1.5 mm² or stranded 25 to 120 mm² (cite:,); finely stranded 16 to 95 mm² (cite:). Auxiliary contacts accept 24 to 16 AWG (cite:). Maximum motor cable length is 300 m (cite:) — keep that in mind for remote motor installations. The unit includes adjustable current limitation (cite:), motor overload protection (cite:), intrinsic device protection (cite:), and supports an external reset (cite:). Minimum load is 20 % (cite:) — do not undersize for a motor drawing less than that fraction of the starter's rating. Inside-delta circuit connection is not supported (cite:).