178B2002 by Danfoss

The 178B2002 is an AC variable-frequency drive manufactured by Danfoss for the VLT 6000 HVAC Drives series. It converts fixed-frequency mains power into a variable output that matches fan or pump demand in building automation systems. By adjusting induction motor speed, it can reduce electrical consumption and mechanical stress in air-handling units, chilled-water pumps, and exhaust systems. This operating approach also helps maintain steadier airflow or water circulation when load conditions change throughout the day. Because the output frequency can be adjusted gradually, connected motors do not need to cycle between full speed and shutdown as often, which can make system response smoother.

This model uses a book-style IP20 housing, which allows side-by-side installation in electrical panels while helping prevent accidental finger contact with live parts. The power section accepts three-phase input from 380-460 VAC, allowing direct connection to common distribution networks in larger facilities. Its inverter stage is rated for 2.2 kW / 3.0 hp, which suits medium-sized blowers and circulation pumps. An integrated EMC stage includes a Class A1 and Class B filter to reduce conducted interference on the supply. The front is supplied without an LCP, so setup and status review require a detachable keypad or remote serial access.

The drive is intended for HVAC service, so its default application focus is on ventilation and pumping duties rather than specialized machine control. Both the application option and the fieldbus interface are supplied with no options, so integration relies on hardwired I/O or an external gateway. That layout is useful in installations where core drive functions are needed without extra communication hardware. The circuit boards have no coating, which means the unit is better suited to clean electrical rooms with limited airborne contamination. The electronics are built as a standard unit, so overload protection, thermal behavior, and fault handling follow the baseline design of this product line.