Manual 2017 Rev C p/n 2017
19
05
Installation
MOTOR DRIVES
Two drive connections commonly used are direct
drive and V-belt drive.
Direct Coupled
When installing the motor directly to the blower,
align the shafts to the coupling according to the
coupling manufacturer’s instructions. Blowers
shipped with the motor directly coupled and
mounted on a common base have been aligned
prior to shipment. Further alignment is not normally
necessary, but be sure to check the alignment and
make adjustments if necessary prior to starting the
blower.
Coupling halves must correctly
¿
t the blower and
drive shafts so that only light tapping is required to
install each half. The two shafts must be accurately
aligned. A direct-coupled blower and motor must
be aligned with the two shafts having no more than
0.005 in. (13 mm) Total Indicator Reading (TIR).
Make sure the face is aligned within 0.002 in.
(0.05 mm).
Establish proper gap between coupling halves
according to the coupling manufacturer’s
instructions with the motor armature. Proper
gap will minimize the chance for end thrust
on the blower shaft. Re-align and grease all
direct-coupled base-mounted blowers after
¿
eld
installation.
V-Belts
If the motor and blower are V-belt connected, the
sheaves on both the motor and blower shafts
should be as close to the shaft bearings as
possible. Blower sheave is not more than 1/4 in.
(6.5 mm) from the blower drive end cover. The
drive sheave is as close to the driver bearing as
possible. Take care when installing sheaves on
the blower and motor shafts. Make sure the face is
accurately in line to minimize belt wear.
Adjust the belt tension to the manufacturer’s
speci
¿
cations using a belt tension tester. Check
new belts for proper tension after 24 hours of run
time. When manufacturer data is not available,
industry guidelines recommend 1/64 in. de
À
ection
for each inch of span (0.157 mm de
À
ection per
centimeter of span) at 8 – 10 lb (3.6 – 4.5 kg) of
force in the center of the belt.
Insuf
¿
cient tensioning is often indicated by slipping
(squealing) at start-up. Do not use belt dressing
on V-belts. Keep sheaves and V-belts free of oil
and grease. Remove tension from belts if the
drive is to be inactive for an extended period of
time. For more speci
¿
c information, consult the
drive manufacturer. In a V-belt drive, the blower
sheave must
¿
t its shaft accurately, run true, and
be mounted as close to the bearing housing as
possible to minimize bearing loads.
A tight or driving
¿
t will force the drive shaft out of
its normal position and cause internal damage. A
loose
¿
t will result in shaft damage or breaking.
Make sure the motor sheave
¿
ts correctly and is
properly aligned with the blower sheave.
Adjust the motor position on its sliding base
so that belt tension is in accordance with drive
manufacturer’s instructions. Always avoid
excessive belt tension. Recheck tension after
the
¿
rst 10 hours of operation and periodically
thereafter to avoid slippage and loss of blower
speed.
Check the blower after installation and before
applying power by rotating the drive shaft by hand.
If the drive shaft does not rotate freely:
• Look for uneven mounting, piping strain,
excessive belt tension, or coupling misalignment
• Check the blower to make sure oil was added to
the reservoirs
