The Siemens 3RW5248-2AC05 is a SIRIUS soft starter rated for a minimum setting current of 240 A, covering motor loads from that floor up to the device's maximum rated current. The 200–600 V operating range means it can be wired into 208 V, 400 V, or 480 V three-phase systems without a transformer — common across North American and European industrial voltages. Trip Class 10A (default), 10E, or 20E per IEC 60947-4-2 governs how long the soft starter allows inrush current before tripping. Class 10A suits standard induction motors starting light loads; Class 20E gives extra time for high-inertia loads like centrifuges or crushers. The default is field-selectable, so one unit covers both duty cycles. The 15 g / 11 ms shock resistance and Pollution Degree 3 rating mean this unit is built for industrial panel environments with conductive dust or occasional condensation — not just clean, climate-controlled switchrooms.
Screw fixing to a vertical mounting surface, rotatable ±90° and tiltable ±22.5° front-to-back. The 210 mm width, 393 mm height, and 203 mm depth require a clear panel footprint; clearance needs are 100 mm above, 75 mm below, 10 mm forward, 5 mm at the sides, and 0 mm backward — plan the gland plate and busbar routing accordingly. Operating ambient -25 to +60 °C, but derate above 40 °C. In a sealed enclosure without forced ventilation, that derating curve is the limiting factor — size the cabinet cooling for the actual motor current, not just the nameplate.
Communications and control features
Built-in support for PROFIBUS, Modbus RTU, Modbus TCP, EtherNet/IP, and PROFINET (with PROFIenergy via the PROFINET communication module). That covers the four major industrial Ethernet and fieldbus ecosystems — no separate gateway needed for most PLC lines. Analog output configurable as 4–20 mA (default) or 0–10 V (parameterizable with the High Feature HMI). Remote reset cycles the control supply voltage. Auto-reset is supported. Pump ramp down and soft torque are built-in — useful for reducing water hammer in pumping stations. Firmware updates are supported. An error logbook is available only with special accessories. The minimum load is 15% of the smallest settable Ie — plan for motor currents below that threshold.