178B1328 by Danfoss

The 178B1328 variable-frequency drive is manufactured by Danfoss within the VLT 6000 HVAC Drives series. It is designed to regulate three-phase induction motors that run fans, pumps, and compressors in building automation systems. By adjusting output frequency instead of allowing across-the-line starts, the drive provides smoother acceleration, reduces mechanical stress, and lowers energy use in ventilation and chilled-water circuits. This operating method can also help reduce pressure shocks in piping and lessen wear on belts, couplings, and other connected mechanical parts.

At a continuous capacity of 45 kW / 60 HP, the unit can support large air-handling sections or condenser pumps without exceeding its thermal limit. The input section accepts utility power from 380-460 VAC, allowing the same model to operate on common 400 V and 460 V networks. The housing uses a compact IP 20 enclosure, so the drive is intended for cabinet installation while still taking up limited panel space. Its circuit boards have a protective coating that helps reduce corrosion caused by humidity and airborne contaminants. Operators use the front-mounted Local Control Panel (LCP) for parameter entry, start and stop commands, and fault-code display.

The drive is intended for HVAC duty profiles and includes predefined proportional-integral regulators for duct static pressure and water differential pressure. The application layer uses standard function blocks, which keeps setup focused on common air and water control tasks. The power hardware is a standard unit, so it does not use a special heavy-duty semiconductor package or an alternate cooling path. The drive is supplied without an internal filter, so installations that require additional electromagnetic noise suppression may need external RFI components or shielded cabling. Optional fieldbus cards can still be added through the reserved interface slot when the system needs network communication with building controls.