Motor starting duty and trip class selection
The 3RW5226-3AC05 is configured with a default trip class of CLASS 10A per IEC 60947-4-2, with selectable CLASS 10E and CLASS 20E for heavier starting profiles. CLASS 10A limits the rotor locked current duration to 10 seconds at the set current limit — a fit for centrifugal pumps and fans where the load torque rises with speed squared, not for high-inertia conveyors that need the extended 20E window. The minimum settable current is 32 A, which sets the floor for the motor FLC the starter can protect. Below that, the overload curve cannot be calibrated to the motor's thermal damage curve, so the driven motor must draw at least 32 A at full load.
Communications and control integration
This SIRIUS soft starter carries onboard PROFIBUS DP, Modbus RTU, Modbus TCP, EtherNet/IP, and PROFINET standard — all five fieldbus protocols are native, no add-on module required for the common plant-floor networks. The PROFINET interface also supports PROFIenergy for coordinated load shedding during production pauses. The analog output is factory-set to 4-20 mA, parameterizable to 0-10 V through the High Feature HMI accessory. This gives the DCS or PLC a live motor current signal without a separate CT loop.
Mounting dimensions and panel clearance
The unit measures 306 mm high, 185 mm wide, and 203 mm deep, with screw fixing to the mounting surface. Clearance requirements: 100 mm above, 75 mm below, 10 mm forward, 5 mm to the side, and 0 mm backward — the back face can sit flush against the panel backplate. Mounting position allows vertical surface orientation with ±90° rotation and ±22.5° tilt forward/back. The 15 g shock resistance at 11 ms holds the contactor closed through a fault event, though above 12 g potential contact lifting is noted — relevant for installations near rotating machinery or on mobile equipment.
Operating temperature and derating
In a non-ventilated enclosure or near a heat source like a drive, the internal temperature rise must be calculated against the 40 °C threshold — above that, the continuous current rating is reduced per the derating curve in the product documentation.