175Z7281 by Danfoss

The 175Z7281 is an AC variable-frequency drive manufactured by Danfoss and positioned within the VLT 6000 HVAC Drives series. This model is intended to regulate induction-motor speed in ventilation, pumping, and other building services so that air or fluid flow matches real-time demand. By modulating output frequency instead of relying on mechanical throttling, the unit improves energy efficiency across HVAC duty cycles and helps reduce wasted power. It interfaces with three-phase motors used in rooftop units, chilled-water pumps, and exhaust fans found in commercial facilities.

The drive accepts a supply range of 380-460 VAC, allowing installation on standard low-voltage three-phase distribution panels. Its motor output capacity is rated at 1.5 kW, equivalent to 2.0 HP, which provides suitable capacity for small to mid-sized fan wheels or circulating pumps. The electronics are housed in a Compact NEMA 1 enclosure that supports indoor mounting while permitting conduit entry from the bottom. A front-mounted LCP interface gives operators parameter access and readouts without external tools. For electromagnetic compatibility, the factory integrates a Class A1 and B filter, enabling conformance with EMC limits in residential and light-industrial zones. No fieldbus options are fitted, so all control is performed through hardwired I/O or the local panel.

In its base configuration, the drive is supplied as a Standard unit. Because there is no coating on the printed circuit boards, the product is intended for clean equipment rooms rather than high-humidity washdown areas. The designated application tag, Graham, identifies the application profile used for typical air-handling sequences such as supply fan ramp-up, economizer control, and night setback. This setup suits building-service applications that require consistent fan or pump response under changing load conditions.