Product Description:

The FC-102P4K is an AC variable frequency drive manufactured by Danfoss as part of the VLT FC 102 HVAC Drives series. It converts fixed-frequency three-phase mains power into a variable-frequency output that lets air-handling units, pumps, and condenser systems run at the speed demanded by a building automation system. By regulating motor torque electronically, the drive replaces mechanical throttling devices and supports energy-efficient flow control in industrial and commercial ventilation systems.

The drive delivers continuous motor power of 4.0 kW, establishing the maximum load it can supply without thermal derating. Command precision begins with an analog input converter that provides 10-bit resolution; each of its 1,024 counts remains within 0.5% full-scale accuracy, supporting stable proportional-integral control loops. Signal flexibility is provided by two analog inputs, so separate temperature and pressure transducers can be read simultaneously. Feedback to the supervisory controller exits the inverter through a 12-bit converter, providing finer resolution for parameters such as motor speed or calculated flow. Two digital transistor outputs and two changeover relay outputs supplement the analog channels with binary run, fault, or frequency-attained indications.

Supplementary process data is sent through one analog output, which can be configured for 0–10 V or 0/4–20 mA operation. The FC-102P4K maintains its electrical ratings at elevations up to 1000 m and across an operating temperature range from 0 °C to 50 °C, allowing installation in rooftop enclosures or equipment rooms without special cooling. Start-stop cycling is limited to two power-ups per minute to protect the DC-link capacitors from excessive electrical stress. Each relay channel can switch control power up to 240 V AC at 2 A under AC-1 duty, allowing direct connection to contactor coils or alarm circuits without intermediate relays.