178B0898 by Danfoss

The 178B0898 variable frequency drive is produced by Danfoss as part of the VLT 6000 HVAC Drives series. It is intended for supply and return fan control, chilled-water pumps, and other HVAC equipment in commercial buildings. By adjusting motor speed in response to analog signals from pressure or temperature sensors, the drive helps maintain stable indoor conditions and reduce power use in air-handling systems. This allows airflow or water circulation to follow changing demand instead of running at a fixed full-speed output. It interfaces directly with standard 0-10 V or 4-20 mA setpoints from building management systems.

Electrically, the drive operates from a three-phase input of 380-460 VAC, allowing installation on common commercial distribution panels. Its output capacity is 2.2 kW / 3.0 HP, which suits small to mid-size fan wheels and centrifugal pumps used on secondary loops. The unit uses an IP20 book-style housing, which keeps panel depth low while permitting finger-safe access when the door is open. This enclosure style also fits narrow cabinet arrangements often used in mechanical rooms. To reduce conducted emissions, the power section includes a built-in Class A1 and B filter, so additional external line chokes are usually unnecessary. Local adjustments, parameter cloning, and basic diagnostics are handled through an LCP (Local Control Panel) mounted on the front of the drive.

The drive includes a Cascade Controller function that sequences multiple pumps or fans according to common setpoints, eliminating separate logic modules. That function can spread operating time across parallel units and add capacity only when demand rises. For installations where moisture and chemicals are minimal, the control board is supplied with no coating, so it should be placed in clean switchgear sections. Networking remains discrete-wire because the stock configuration has no fieldbus communication options. The electronics are supplied as a standard unit, which follows the baseline build for this product platform.