The Siemens 3RW5558-2HA14 is a SIRIUS-series soft starter rated for 200-480 V supply, designed to ramp induction motors up to speed and protect them during start and stop cycles. Its trip class is configurable — CLASS 10A / 10E (default) / 20E / 30E per IEC 60947-4-2 — so you match the thermal protection to the load: 10A for standard starts, 20E or 30E for high-inertia loads like centrifuges or crushers that need a longer acceleration window.
The rated voltage range of 200-480 V covers the common 230/400/480 V three-phase networks across Europe and North America. At 50 Hz the control supply accepts 110-250 V; at 60 Hz the same range applies — no separate control transformer needed for most panel voltages. Physical footprint is 478 mm wide, 764 mm high, 241 mm deep. Clearance requirements: 100 mm upwards, 75 mm downwards, 10 mm forwards, 0 mm backwards, 5 mm at the side. That backwards zero means it can sit flush against a back panel, saving enclosure depth — useful when retrofitting into existing MCC buckets. Fieldbus support includes PROFIBUS, Modbus RTU, Modbus TCP, and EtherNet/IP, plus PROFIenergy in conjunction with PROFINET communication modules. This makes it straightforward to integrate into Siemens S7 or Rockwell ControlLogix architectures without a protocol gateway. Motor control features include DC braking, voltage ramp, pump ramp down, torque control, breakaway pulse, and combined braking — covering soft start, soft stop, and controlled deceleration for pump, fan, and conveyor applications. The analog output is configurable 4-20 mA (default) or 0-10 V, useful for feeding motor current or torque to a PLC or HMI.