175H1236 by Danfoss

The 175H1236 is an AC motor drive produced by Danfoss as part of the VLT 3000 Variable Speed Drives series. It is intended to regulate three-phase induction motors in automated plant equipment, allowing speed control, soft starting, and controlled braking to match process demands while reducing mechanical stress and energy consumption. This arrangement makes the unit suitable for systems that need adjustable motor performance during normal production cycles.

This drive is designed for repetitive energizing cycles up to 5 times per minute and accepts two input operating classes. In constant-torque mode, the maximum input current is 30.7 A; in variable-torque mode, it rises to 41.5 A. Corresponding output capability reaches 23.0 kVA in constant-torque operation and 31.6 kVA when the application follows a variable-torque profile. Under the variable-torque setting, the inverter can deliver a continuous motor phase current of 44 A, supporting larger fan or pump loads without derating. The allowed switching rate helps prevent contact wear on upstream disconnectors, while a permitted conductor cross-section up to 6 AWG simplifies connection to existing motor feeders and minimizes voltage drop at full load.

Dynamic performance is anchored by a maximum carrier-regulated output frequency of 500 Hz, giving a wide speed range for high-pole motors. Line protection guidelines call for a main pre-fuse rated at 63 A to clear severe faults while avoiding nuisance trips during inrush events. For short overloads, the inverter can source 51.2 A for 60 seconds, allowing the driven machine to overcome brief torque peaks such as cold starts. Acceleration and deceleration slopes are fully adjustable up to 3600 s, enabling gentle ramping of conveyors or critical fluid systems. These adjustable ramps and the short-term overload capability support applications that need controlled starts, stops, and brief torque reserve.