Fans for air handling systems
Specific air volume and pressure requirements are met by a fan and motor assembly mounted on an independent sub-frame. Noise and vibration transmission is prevented by an anti-vibration mount isolation from the main unit frame coupled with a flexible connection on the fan discharge.
Customers can choose from a comprehensive range of fan types including centrifugal forward and backward curved fans, plug, axial or mixed flow fans. Special finishes, construction and control elements can be incorporated to meet certain specifications or applications. If direct drive fans are installed, anti-vibration mounts can be fitted in accordance with the type of fan and application involved.
Standard specification motors are aluminium or steel frame cage rotor type motors for which various speed control options are available.
Motors of up to and including 5.5kW in size are suitable for D.O.L. starting, while those above 7.5kW are appropriate for Star-Delta starting.
Motors complying with Class F insulation to BS 2757 with an IP54, TEFV enclosure are supplied as standard, although Thermistor protection set to operate at no more than 120 degrees C so as to comply with BS 4999: part 72 can also be provided.
The fan motor drive is typically a pulley belt drive with taper lock pulley for motor ratings up to and including 30kW. Where drives exceed 30kW capacity key secured pulleys are used.
At least two endless V belts, manufactured in line with BS3790 and utilising A, B or C sections, are deployed on each drive along with close grained, cast iron machined pulleys. As a key safety benefit, the fan section of all Jet AHUs is supplied with a secondary guard to prevent direct access to the fan drive.