Electric Fan GFRP-52'' --HIGH PERFORMANCE AND INNOVATIVE DESIGN: --Heavy galvanized motor mount straightens the air as it is propelled through the venturi. --Extremely quiet operation on all speeds. --Automatic belt tensioner. --Totally enclosed high efficient motor. --Easy to remove plastic shutter design. --Heavy corrosion resistant fiberglass housing. --Shipped fully assembled except of discharge cone and guard. --Heavy duty pulley and bearing assembly. --Optional soft start variable frequency drive increases bearing,belt and motor life. FEATURES: --Balanced 72'' heavy duty corrosion resistant 6 paddle aluminium. --On high speed produces 55,000 CFM and 25 CFM/watt at "0" static pressure. --on low speed produces 10,000 CFM and 20 CFM/watt at "0" static pressure. --Optional variable frequency drive allows you a smooth speed adjustment from 300 RPM down to 80RPM.Fan power consumption reduces with speed.Make sure you have a minimum shutter opening on low speed of "1". Technical Specifications: GFRP-52'' TypeDimension (mm)Blade Size (mm)Speed (r/m)Air Flow (m3/h)Power (Kw)Voltage (V)HzPhaseGFRP-52825x1545x15341320480550001.1230/380/415/46050/601 or 3