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9. MAINTENANCE [How to Service the Air Compressor]
If the dust adheres to main motor fin, cooling
performance for main motor is decreased. It may cause
shorten the main motor life and/or relative parts failures.
The illustration below shows the main motor of a Vtype
as a sample.
①
Turn off the power and remove the right cover [Ref.
No. 908]. Then remove the motor duct [Air-Cooled
Ref. No. 975, Water-Cooled Ref. No. 975 - 978]. The
main motor and cooling fin are very hot soon after the
air compressor is stopped. Wait until they are cooled
down properly before starting the cleaning.
②
Check the main motor cooling fin for dust and dirt.
Blow the cooling fin by dry air using an air blow
nozzle with a bent end. Since the main motor has
temperature sensor, be careful NOT to cut its wiring
and ensure that the dust and dirt is NOT adhered to
the surface of each sensor.
③
Install the covers to their original locations.
DCBL motor thermistor
Air blow nozzle
14
Cleaning of Main Motor Cooling Fin
15
Inspection of Fan Inverter
①
Turn off the power and wait approximately 10
minutes. Next, remove the front door and then
remove the cover of control panel
②
Check that the charge light of the fan inverter is off.
Check for abnormal overheat, discoloration, abnormal
odor, and contamination.
③
Blow off the dust by dry air
④
During periodical maintenance, re-tighten the
terminals, check the conductor and insulator for
corrosion, and inspect/replace the cooling fan and
smoothing capacitor.
Contact the local HITACHI distributor/master dealer or
representative office for the detail.
Charge lamp
(Fan inverter)
(Check that it is off.)
[Fixed-Speed type]
Air-Cooled
Air blow nozzle
16 to 20 inches
(400 to 500) mm
Bend the nozzle at 0.8 to 1.8 inches
(20 to 40 mm) from the end to
facilitate cleaning.