175H1025 by Danfoss

The 175H1025 is a variable frequency drive produced by Danfoss and is part of the VLT 3000 Variable Speed Drives series. The unit modulates the voltage and frequency supplied to an induction motor so plant operators can match shaft speed to process demands, reduce energy consumption, and limit mechanical stress during starts. Integrated within automation panels, it interfaces with field I/O through 24-volt contacts and supplies regulated three-phase output that follows setpoints from PLCs or analog references.

This drive draws its main power from a three-phase mains of 400 V (3-phase), so control cabinets must provide that line-to-line voltage. Under continuous torque mode, the inverter can deliver 2.8 A to the motor, while its short-term overload rating rises to 3.5 A for 60 seconds to handle starting inertia. Apparent power at rated load is 2.0 kVA, a value used to size upstream contactors and cabling. Logic and relay circuitry are supplied separately with 24 V DC, isolating control electronics from the mains section. To protect the drive from fault currents, a line fuse of 16 A is recommended; coordinating that fuse with the drive's semiconductor rating prevents nuisance trips and blocks destructive overcurrents.

The housing carries an IP21 rating, allowing vertical mounting inside clean electrical rooms where dripping water and large foreign objects are absent. Noise suppression is aided by an integrated RFI filter, so additional external filters are often unnecessary for EMC compliance. For motor leads, the unit supports screened cable runs up to 150 m and unscreened runs up to 300 m, giving flexibility in conveyor lines or remote pump stations. With a typical motor power of 1.1 kW, these distance limits permit full torque delivery without unacceptable voltage drop.