178B8577 by Danfoss

The 178B8577 is a low-voltage variable frequency drive produced by Danfoss and supplied in the VLT 2800 Low Voltage Drives series. The drive converts fixed-frequency three-phase mains power into a variable output that governs the speed of induction motors in automated plants. This operating method lets connected motors match process demand more closely than fixed-speed operation. Its narrow form factor allows installation in crowded control cabinets, where accurate motor torque control can reduce energy use and mechanical wear on pumps, fans, and small conveyors.

This model delivers a nominal output of 0.55 kW, which is equivalent to 0.75 HP, making it suitable for fractional-horsepower machinery. It accepts a supply of 380-480 V ±10% 50/60 Hz on a three-phase line and adjusts the output frequency accordingly. The IP20 open-chassis design channels heat into the enclosure, so forced ventilation is recommended. Because the unit is supplied without an EMC filter, external RFI suppression must be provided to meet emission limits. Overvoltage generated during braking is dissipated by the integrated chopper, which works with the standard brake circuit to support rapid stops in fast-cycle duties.

The drive is intended for process applications, and its mechanical and interface features support that role. The slim book-style housing mounts beside other drives without widening the panel. A factory-applied protective coating helps guard the electronics against moisture and airborne chemicals common in batching areas. Operators set parameters through the built-in display (SLCP), which provides immediate feedback on status and alarms. Quick deceleration is supported by the standard brake configuration, and no application option or fieldbus board is installed, so integration relies on hard-wired I/O for simple standalone skids.