What this soft starter covers
The Siemens 3RW5075-2TB05 is a SIRIUS hybrid soft starter rated for a minimum operating current of 160 A and a supply voltage range of 200 to 600 V. It's built for three-phase induction motor starting in applications where controlled acceleration and deceleration reduce mechanical shock and electrical stress on the line. Trip class is selectable between CLASS 10A, 10E (preset), and 20E per IEC 60947-4-2 — that sets the thermal overload protection timing for the motor. CLASS 10A suits standard-start loads; CLASS 20E gives more headroom for high-inertia starts like centrifuges or crushers. ATEX and IECEx certification (both listed as Yes) means this unit can be installed in Zone 1 or Zone 2 hazardous areas with explosive atmospheres — a key differentiator from standard soft starters that lack the Ex marking.
Fastening method is screw fixing — it bolts to a backplate, not a DIN rail. The envelope is 282 mm deep × 160 mm wide × 230 mm high, so plan the cutout and clearance accordingly. Mounting position allows a vertical mounting surface with ±90° rotation and ±22.5° tilt forward/backward. Clearance requirements: 100 mm upwards, 10 mm forwards, 0 mm backwards, 75 mm downwards, and 5 mm at the sides.
Networked control and starting profiles
Fieldbus support covers PROFIBUS, Modbus RTU, Modbus TCP, EtherNet/IP, and PROFINET (with PROFIenergy capability via the PROFINET communication module). That makes it straightforward to integrate into most plant networks without a separate gateway. Starting profiles include Soft Torque, Voltage Ramp, and Pump Ramp Down — the pump ramp-down feature is specifically useful for preventing water hammer in pump applications. Remote reset is available by cycling the control supply voltage. Minimum load is 15 % relative to the smallest settable Ie — so it can handle lightly loaded motors without nuisance tripping. Auto-reset is enabled, which helps in unattended installations.
Approvals and compliance documentation
The unit carries CE marking, UL approval, and CSA approval — accepted across North American and European installations. ATEX and IECEx certification are also confirmed. Shock resistance is 15 g / 11 ms, with potential contact lifting from 12 g / 11 ms — relevant for mobile or high-vibration environments.