The Siemens 3RW5525-1HA14 is a SIRIUS 3RW55 soft starter that controls motor acceleration and deceleration for three-phase induction motors in the 200 to 480 V range. It is a current-production part (lifecycle stage: current) and carries ATEX and IECEx certification for use in potentially explosive atmospheres, plus UL and CSA approvals for North American installations. Trip class is configurable: default CLASS 10A or 10E, with options for 20E or 30E per IEC 60947-4-2. That means you can match the thermal overload protection to the motor start profile — fast starts (CLASS 10) for normal loads, slower starts (CLASS 20/30) for high-inertia loads like fans or centrifuges.
Rated voltage 200-480 V covers common low-voltage three-phase supplies worldwide. The control supply is 110-250 V AC at both 50 and 60 Hz, so it works on either mains frequency without a transformer change. Screw terminals simplify field wiring — no special crimp tooling needed. The enclosure dimensions are 306 mm high, 185 mm wide, 203 mm deep. Clearance requirements: 100 mm above, 75 mm below, 10 mm in front, 5 mm at the sides, 0 mm behind. That 0 mm rear clearance means it can sit flush against the back panel, saving depth in the enclosure. Analog output is configurable as 4-20 mA (default) or 0-10 V, giving a direct signal to a PLC or drive for current/load monitoring without an external transducer.
Fieldbus and control integration
Built-in support for PROFIBUS, Modbus RTU, Modbus TCP, and EtherNet/IP means this soft starter drops into most industrial networks without a separate gateway. PROFIenergy is available when paired with PROFINET High-Feature communication modules. Additional control features include DC braking, voltage ramp, pump ramp down, torque control, breakaway pulse, and motor heating — covering soft-start, soft-stop, and jogging for conveyors, pumps, and fans.