Soft starter for motor starting duty
The 3RW5235-2AC04: It is designed for controlled starting and stopping of three-phase induction motors, reducing inrush current and mechanical stress on the driven load. Trip class is configurable between CLASS 10A (default), 10E, and 20E per IEC 60947-4-2, meaning the overload protection can be tuned to the motor's thermal time constant — CLASS 10A for standard starting, 20E for high-inertia loads that need a longer acceleration ramp. This matters for panel builders sizing the enclosure ventilation — the derating curve in the manual governs the continuous current rating at elevated ambient.
Fieldbus and control connectivity
The 3RW5235-2AC04 supports PROFIBUS, Modbus RTU, Modbus TCP, EtherNet/IP, and PROFINET standard communication, giving it broad compatibility with most industrial control networks. PROFINET also supports PROFIenergy for energy management during idle phases. Analog output is 4-20 mA (default) or 0-10 V (parameterizable with High Feature HMI), providing a process signal for PLC monitoring of motor current or load. Remote reset is supported by cycling the control supply voltage. Features include soft torque for gentle starts, pump ramp down for controlled deceleration of centrifugal loads, and an error logbook (requires special accessories) for fault diagnostics.
Mounting is by screw fixing with a vertical mounting surface; the unit can be rotated ±90° or tilted ±22.5° front-to-back, offering flexibility in panel layout. Dimensions are 306 mm height, 185 mm width, and 203 mm depth — allow for the specified clearance: 100 mm upwards, 75 mm downwards, 10 mm forwards, 5 mm at the side, and 0 mm backwards for airflow and wiring access. Shock resistance is 15 g / 11 ms (from 12 g / 11 ms with potential contact lifting), so the unit is suitable for industrial environments with moderate vibration, but the mounting bracket and panel must be stiff enough to avoid resonance at those levels.
The 3RW5235-2AC04 carries UL, CSA, and CE marking, covering North American and European regulatory jurisdictions. Degree of pollution is 3 per IEC 60947-4-2, meaning it is rated for conductive pollution environments typical of industrial control panels.