- 11 -
If the rotation direction is opposite, switch off the main power. Swap the connections of two of the
three power cables. Then test operation again and check the rotation direction. Since the wire
color and power source phase may vary according to the power company, rotation may be
opposite even if the matched wire colors are connected. When first applying power, be sure to
check the rotation direction.
If no abnormalities are found during momentary operation, start continuous operation. Record that
there are no abnormal noises, measure and record the vibration value and current value, and
check whether they are acceptable or not.
When using a flow volume adjustment damper, set it to full open before starting, and then after
starting gradually close the opening. When closing and opening the damper, there may be an
increase in noise or vibrations or a drop in pressure. If this occurs, do not close the opening
further; instead, open it more. These phenomenon are due to stall operation. For these reasons,
controlling the flow volume by adjusting the impeller blade angle or by inverter speed control is
recommended instead of using a damper.
5 Operation
5.1
Operation, maintenance, and inspection
Periodic maintenance and inspection are required to operate the blower safely. If the daily inspection is
performed on the following items and the results are recorded, abnormalities can be detected early to
prevent problems.
1
)
Check for vibration or abnormal sound once every three months and inspect the insulation once a year.
Inspect the motor while referring to its instruction manual.
2
)
It is recommended to replace the shaft seal or packing at the same time as the bearing is replaced even
though the replacement cycle may vary depending on the deterioration status or operating
environment.
3
)
When the blower used is an air-cooling type or quasi-moisture-proofing type blower, or when air
containing dust is taken in, gas contact parts (e.g., inside of the casing, impeller, etc.) can be badly
corroded and the rotation contact portion can be significantly worn. Therefore, the inspection cycles
should be shortened.
Inspection item
Recommended inspection cycle
Inspection contents
3 months
6 months
12 months
Con
dition inspectio
n
Abnormal
noise
Blower
■
□
□
Check for abnormal noise due to rattles.
Check for metal contact noise.
Check for other noise considered to be
abnormal.
Motor
■
□
□
Check the grease.
Check for loose bolts.
Check the bearings for abnormal noise.
Vibration
■
□
□
Check the vibration value and any changes to
it.
Temperature
■
□
□
Check the temperature near the bearing and
any changes to it.
Electrical section
□
■
□
Check the current value and voltage value,
and any changes to them.
Comp
one
nt
in
sp
ec
tion
Coupling
Rubber bushing
□
■
□
Check for hardening.
Check for wear or cracks.
Anti-vibration
rubber
□
■
□
Check for hardening.
Check for wear or cracks.
Shaft seal
□
□
■
Check for cracks or damage.
Packing
□
□
■
Check for damage or hardening.