Arrangements

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

Arrangement 1 – Belt Drive

Overhung wheel on shaft and bearing assembly isolates fan bearings from the airstream. Motor mounts independently from fan.

Arrangement 3 – Belt Drive

Wheel supported between bearings is compact and suitable for clean, dry-air service.

Arrangement 4 – Direct Drive

Wheel mounted directly on motor shaft to provide the most compact design. Elimination of shaft and bearings for minimum maintenance. Temperature restriction of 180° F due to close proximity of the motor to the housing.

Arrangement 4V – Direct Drive

Wheel mounted directly on motor shaft to provide the most compact design. Elimination of shaft and bearings for minimum maintenance. Motor shaft is vertically oriented. Temperature restriction of 180° F due to close proximity of the motor to the housing.

Arrangement 7 – Direct Drive

Wheel supported between bearings is compact and suitable for clean, dry-air service.

Arrangement 7 – Direct Drive (shown with optional inlet box)

Wheel supported between bearings is compact and suitable for clean, dry-air service. An optional inlet box may be purchased to allow for bearings to be placed outside the airstream.

Arrangement 8 – Direct Drive

Integral pedestal furnished for the motor and coupling. Most flexible of the direct drive arrangements allowing for larger motors, fan sizes and accessories.

Arrangement 9 – Belt Drive

An adjustable motor mount featured on this arrangement provides a compact grouping of motor, drive belt and fan. Similar to Arrangement 1, but with motor mounted on side of fan pedestal reducing overall size and field-installation costs.

Arrangement 10 – Belt Drive

Compact, packaged design with motor mounted within the fan pedestal. Minimum field installation labor required.

Centrifugal fans are offered in other arrangements in the market, but only those offered by Industrial Air Technology Corp. are listed here.