Product Description:

The 175G5525 soft starter is produced by Danfoss within the MCD Soft Starters series. This solid-state device is installed in motor feeder panels to ramp three-phase induction motors up to speed while limiting mechanical shock and mains inrush current. By adjusting thyristor conduction angles and providing auxiliary control signals, it supports conveyor, pump, and compressor applications in general industrial automation.

At the control terminal, the starter delivers a regulated 200 mA, 24 V DC supply for external sensors and maintains an analog feedback tolerance of ±5% when monitoring motor current or torque references. The analog output can drive loads up to 600 Ω, allowing direct connection to most PLC analog inputs without buffering. For delta-connected motors, its AC53b duty rating is 32 A (3-30:330), indicating operation at three times the rated current for 30 seconds with 330 seconds between starts. Surge immunity is reinforced by an impulse withstand rating of 4 kV, reducing the risk of thyristor mistriggering during line transients. A separate accuracy tolerance of ±10% applies to the 24 V DC source. Insulation to ground is rated at 690 V AC.

When wired in-line, the unit has an AC53b duty rating of 21 A (3-30:330), and its continuous full-load current range extends from 5 A to 23 A to accommodate smaller motors. The assembly can tolerate prospective fault currents up to 65 kA when coordinated with suitable upstream fuses and circuit breakers. Its IP20 enclosure provides protection against accidental finger contact but requires installation inside a cabinet in dusty or wet locations. The internal SCR stack can withstand 1,150 A²s of I²t energy. A relay contact rated for 10 A at 250 V AC is available for run-status or fault signaling. The maximum delta full-load current is 34 A, while the thermal mass and heat sink design keep the total mass at 4.2 kg for easier panel mounting and handling.