Panel fit and motor ratings
The Siemens SIRIUS 3RT6028-1BM40 is a size S0 power contactor. It measures 45 mm wide by 85 mm tall by 107 mm deep. Side-by-side mounting is allowed. For motor duty, the AC-3e rating at 60 °C ambient is what matters: 15.5 kW at 230 V, 27.5 kW at 400 V, and 47.5 kW at 690 V. The maximum switching voltage for AC-3 and AC-3e duty is 690 V. That 27.5 kW at 400 V covers a standard 37 kW motor frame derated for a warm panel — typical for conveyor drives or pump starters on a 400 V three-phase line. The rated insulation voltage is also 690 V, so it's comfortable on 480 V or 575 V systems within the voltage limits.
Lifecycle and sourcing reality
Compliance documentation is in order: the substance prohibition date is 05/01/2012, which aligns with RoHS and REACH requirements. The brand is Siemens SIRIUS, so you get the full IEC and UL documentation package on request.
Terminals and auxiliaries
Main and auxiliary/control circuits use screw-type terminals. Main terminals accept 2x (0.5 to 1.5 mm²) solid or stranded, or 2x (0.75 to 2.5 mm²).
Environmental and switching life
Operating temperature range is -25 to +60 °C; storage range is -55 to +80 °C. Pollution degree 3 means it's rated for industrial environments with conductive pollution — no special coating needed in a standard panel. Mechanical life is typical 10 million operations. Maximum switching frequency varies by duty: 1,000 cycles/hour at AC-1, 750 at AC-3 or AC-3e, 250 at AC-4, and 1,500 at DC. The 24 V coil draws 6 A; at 230 V it draws 10 A; at 110 V it draws 1 A; at 220 V it draws 0.3 A; at 400 V it draws 3 A; at 690 V it draws 1 A.