Product Description:

The 175G5302 is a solid-state soft starter manufactured by Danfoss as part of the MCD Soft Starters series. It is installed between the incoming line and a three-phase induction motor to limit voltage during startup, which reduces mechanical shock and line-side current peaks that can affect upstream protection devices. In typical fixed-speed machinery, this helps reduce belt slap, gearbox shock, and stress on couplings during acceleration. This model belongs to the VLT Soft Starter MCD product group and is intended for equipment that benefits from controlled acceleration without the added complexity of a variable-frequency drive.

The unit can pass a continuous motor current of 75 A, matching its power capability of 37 kW on standard industrial loads. It accepts a line supply of 200–440 VAC and shapes that voltage over a preset 0.4 s ramp-up time so belt drives, gearboxes, and couplings experience less shock at startup. During the voltage ramp, the starter delivers an initial torque of 70% of rated motor torque, which is enough to overcome static friction while still moderating mechanical stress. Because a soft starter only manages starting current and torque, the motor continues to run at full line frequency once the start sequence is complete.

The control electronics can be powered from either 110/240 VAC or 440 VAC, allowing the same starter to be wired into low- or high-voltage control circuits without a transformer. Its duty classification is AC53b 4-6:594, which indicates a repeated-start operating profile for enclosed devices. Main conductor terminations are tightened to 4 Nm, while the low-power terminals for start-stop commands and status relays are secured at 0.5 Nm to maintain reliable clamping force on copper conductors. This model does not include a soft-stop function, so deceleration is handled by the motor and load inertia rather than by controlled phase reduction.