Product Description:

The Danfoss 175G5219 soft starter belongs to the MCD Soft Starters series. As a member of the MCD 202 line, it is installed in the motor supply circuit of a three-phase power system to ramp voltage smoothly during start and stop. That controlled ramp reduces sudden torque changes at the shaft and helps limit line disturbances on the incoming supply. It is suited for applications such as pumps, compressors, and conveyors where predictable acceleration and deceleration help protect connected mechanical parts.

The control board accepts a 110/240 VAC or 440 VAC auxiliary feed, allowing the same unit to operate from common control transformer voltages. The main three-phase circuit is rated for 200-440 VAC, enabling direct connection to widely used low-voltage mains. During heavy-duty sequences, the SCR stack carries 165 A for 20 seconds, whereas normal-duty profiles permit 200 A for 6-second starts; both operating envelopes correspond to the 110 kW motor power rating at 40 °C. Conduction losses fall to only 10 W once the internal bypass relays close, which reduces heat after the motor reaches running speed. Thermal loading during each start is 3 W per ampere. A thermistor cutout opens at 2.8 kΩ for semiconductor protection, the silicon bank withstands 320,000 A²s of I²t energy, and an auxiliary main output relay rated at 6 A can drive a bypass contactor or status lamp.

The chassis has an IP00 protection class, so it must be enclosed to prevent accidental contact with live parts. Because the housing is open, the starter is normally mounted inside a suitable electrical cabinet. Installation weight is 6.8 kg, which supports panel mounting without extra supports. The unit is rated for AC53b 4-20:580 heavy-duty operation and AC53b 4-6:594 normal-duty operation, covering the allowed on-time, off-time, and start current. The power circuit tolerates fault currents up to 10 kA at 440 VAC.