Motor starting duty and trip class selection
The 3RW5235-6TC15 is a SIRIUS hybrid switching device — a soft starter that ramps motor voltage during start to limit inrush current and mechanical shock. Its trip class is configurable: CLASS 10A (default), 10E, or 20E per IEC 60947-4-2, which sets the maximum allowable start time before the overload protection trips. For a pump or conveyor with a high-inertia load, selecting 20E gives a longer acceleration window; for a compressor that starts unloaded, CLASS 10A keeps the protection tight. Rated supply voltage spans 200 to 600 V, covering 208 V, 400 V, and 480 V systems common in North American and European panels. The minimum settable motor current is 68 A, so the soft starter fits motors in the 30–50 kW range at 400 V, depending on the service factor and ambient derating.
Fieldbus connectivity and panel integration
This soft starter ships with onboard PROFIBUS, Modbus RTU, Modbus TCP, EtherNet/IP, and PROFINET standard communication — no separate gateway module needed for most automation architectures. PROFIenergy is supported when used with the PROFINET standard communication module, allowing energy-saving shutdown of the motor during idle periods. Mounting is screw-fixing to a vertical surface, with the unit rotatable ±90° and tiltable ±22.5° front-to-back. Clearance requirements: 100 mm above, 75 mm below, 10 mm forward, 5 mm at the sides, and 0 mm backward — so it can sit flush against the back panel. Dimensions are 185 mm wide, 306 mm high, and 203 mm deep, which fits a standard 600 mm deep enclosure with room for cable glands.
Application features and ambient derating
Soft Torque and Pump Ramp Down are built in — these reduce pressure surges in pumping systems during start and stop, which extends the life of valves and piping. The unit also supports auto-reset and remote reset by cycling the control supply voltage, useful for unattended installations. The shock resistance is 15 g / 11 ms, dropping to 12 g / 11 ms if potential contact lifting is a concern — relevant for installations on vibrating machinery.