Mitsubishi Electronics MD-CX522-04K to s.7K Building Set User Manual


 
6. TROUBLESHOOTING
6-9
6
NOTICE
Insulation resistance test using megger
Where possible, do not conduct an insulation resistance test using a
megger since an insulation test has been done before shipment
from the factory. When it is inevitable to make an insulation
resistance test using a megger, disconnect all cables from the
control circuit to prevent a test voltage from leaking into the control
circuit. The drive unit will fail if the test voltage is applied to the
control circuit.
R
S
T
U
V
W
M
Moto
r
Power supply
500VDC
megger
Drive unit
Earth terminal
Pressure test
Do not conduct a pressure test. A pressure test can deteriorate the
semiconductor parts in the drive unit.
6.3.2 Wear parts
The replacement lives of the parts are as indicated below. Since the lives vary
with the operating environment and/or usage, you must replace the parts if you
have found any fault during periodic inspection or the like.
Part Name
Standard
Replacement
Intervals
Method Remarks
Cooling fan 2 to 3 years
Change
(as required)
The bearing life of the cooling fan is 10,000 to
35,000 hours. For continuous operation,
therefore, normally replace the fan every 2 to
3 years as a guideline.
Main circuit
smoothing
capacitor
5 years
Change
(as required)
On-board
smoothing
capacitor
5 years
Change
(as required)
The life greatly depends on the ambient
temperature and operation specifications of
the drive unit. When continuous operation is
performed in normal air-conditioned
environment, the life is approximately 5 years.
The life halves for each 10
°
C rise in ambient
temperature.
The capacitor deteriorates rapidly after the
given period has elapsed, causing the motor
to run unstably or activating the overcurrent
protective function.