The term “Arrangement” is used to describe position of the motor relative to the fan. Main criteria which may influence your choice:

  • Fan performance (temperature, contents of airstream, etc.)
  • Size/location (footprint size of unit, access to various components on the fan, etc.).
  • Drive method (belt or direct)

Belt Drive Pros:

  • Allows fan to operate at “non motor” speeds
  • Easier to change fan speed & performance
  • Motor positioning flexibility

Belt Drive Cons:

  • Requires more maintenance
  • Possible drive losses due to belt slippage
  • May have horsepower limitations

Direct Drive Pros:

  • Usually more compact (size/footprint)
  • Less components to maintain/balance
  • No drive losses

Direct Drive Cons:

  • VFD required to change speed or performance
  • More expensive to change speed or performance
  • Precise alignment of motor/coupling/shaft is critical
  • Without a VFD, fan selection is limited to motor speed