The Fuji FRN300AR1S-5U is a 300 HP, 575 V three-phase inverter from the FRENIC HVAC series, purpose-built for variable-torque loads like large centrifugal fans, pumps, and cooling towers in commercial HVAC or industrial air-handling systems.
At 300 HP on a 575 V three-phase supply, this drive is sized for a motor drawing roughly 300 A full-load current on a 575 VAC bus — typical for a 250–300 kW fan or pump in a 480 V plant stepping up through a transformer, or direct-fed on a 575 V Canadian / 600 V class industrial service. The FRENIC HVAC series is tuned for variable-torque profiles: quadratic V/f curves, built-in PID for duct static pressure or differential temperature control, and sleep/wake functions for low-load periods — not a general-purpose drive for constant-torque conveyors or hoists.