The Siemens 3RW5072-2AB14 is a SIRIUS-series soft starter rated for motor control on 200–480 V AC lines, with a minimum settable current of 90 A. It carries ATEX, UKEX, and IECEx certification, so it is specified for hazardous-area motor starting — think pumps, fans, or conveyors in Zone 1/21 gas or dust environments where standard starters cannot go. The trip class is selectable between CLASS 10A, 10E (preset), and 20E per IEC 60947-4-2, which governs how quickly the overload protection responds to a stalled rotor or locked-rotor condition. A 10A trip clears a cold start in under 10 seconds at 7.2× Ie; 20E gives you more headroom for high-inertia loads like centrifuges or long conveyor belts.
Communication and control options
On the control side, this unit comes with PROFIBUS onboard and also supports Modbus RTU, Modbus TCP, and EtherNet/IP — so it drops into most fieldbus architectures without an extra gateway. The analog output is configurable as 4–20 mA (default) or 0–10 V via the High Feature HMI, which gives you a real-time current signal back to the PLC for load monitoring. A remote reset is possible by cycling the control supply voltage, and the unit supports auto-reset, soft torque, voltage ramp, and pump ramp down — useful for reducing water hammer in pumping stations. Note that the error logbook is available only with special accessories, and the HMI-High Feature interface is not fitted on this variant.
Mounting is screw fixing — no DIN-rail clip on this frame size — so plan for a backplate or sub-panel. The dimensions are 160 mm wide by 230 mm high by 282 mm deep, with clearance requirements: 100 mm upward, 75 mm downward, 10 mm forward, 0 mm backward, and 5 mm at the sides. Shock resistance is 15 g / 11 ms, dropping to 12 g / 11 ms if contact lifting is a concern. The service factor is 1, meaning no built-in overload margin beyond nameplate.