178B2007 by Danfoss

The 178B2007 is an AC variable-frequency drive produced by Danfoss for the VLT 6000 HVAC Drives series. It converts fixed-frequency mains power into a modulated output for speed control of induction motors used in air handlers, chillers, and pump circuits. Instead of running motors continuously at line speed, the drive adjusts output frequency to match system demand. This helps improve energy efficiency and maintain steadier airflow or fluid pressure in building automation systems. It is suitable for variable-speed operation where loads change throughout the day.

This model operates from a supply of 380-460 VAC, allowing connection to common three-phase distribution networks without an autotransformer. Its motor capacity is rated at 3.0 kW, or 4.0 HP, so it can drive mid-sized fan wheels or centrifugal pumps in branch loops. The slim Bookstyle housing carries an IP 20 rating, which protects internal boards against accidental finger contact when the drive is panel mounted inside a climate-controlled electrical room. An integrated Class A1 and B filter attenuates conducted electromagnetic noise to help limit emissions in residential and commercial installations. The drive ships without an LCP, so changes must be made through a remote keypad or a PC setup tool connected through the front service port.

For HVAC applications, the default control macros emphasize proportional-integral regulation of temperature and static pressure. There is no coating on the control boards, so the enclosure should remain in low-condensation areas to reduce the risk of corrosion on fine-pitch components. The fieldbus slot has no options installed, which leaves room for a later BACnet, LonWorks, or Modbus card if networked control is needed. This arrangement supports standalone operation until a communication card is added. Internally, it is the standard unit, so the IGBT bridge, brake chopper, and logic supply follow the baseline thermal and electrical limits for this frame size.