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Table 30. Initial inspection
Time of initial inspection Major inspection items
Immediately
before
･ Check whether screws are fully tightened.
Confirm not only the terminals to which wires
are connected but also those to which no
wire is connected.
･ Check whether small items such as a screw,
washer, chip, wire waste, etc. have infiltrated
the switch.
･ Check whether there is any erroneous wiring.
Starting time of
operation
Immediately
after
･ Check whether the contactor is closed per-
fectly .
･ Check whether the electromagnet produces
abnormal beats.
･ Check whether there occurs instantaneous
arcing from arc suppressing chamber due to
starting current of motor when closing the
contactor. If the arcing is greater than at the
breaking time, it is necessary to check.
After entering normal operation,
･ 3 to 10 days after
･ 3 months after
･ Check screws for loosening.
･ Check whether dust or oil are adhering to any
part. If any foreign matter is found to be
adhering, investigate the cause.
･ Turn off the power and move the moving part
by hand.
･ Check whether the contact is worn. If abnormal
wear is found, investigate the cause.
･ Re-confirm the inspection items required
immediately before and after operation.
(2) Periodical inspection
(a) Time of periodical inspection
When the inspection is carried out taking into consideration the environment and the frequency of use as given
in Table 31 , appropriate security and prevention may be expected.
Table 31. Time of periodical inspection
Interval of periodical inspection Environment of use
Contact part Operating part
A clean and dry place Every 12 to 36 months
A place which is relatively free of dust,
humidity, salt, corrosive gas, vapor, etc.
Every 12 months
Inspection time
according to
environment
Places other than the above. Every 3 to 6 months
100-times/hr (30,000-times/month) or less Every 12 months Every 36 months
200-times/hr (60,000-times/month) or less Every 6 months Every 24 months
600-times/hr (200,000-times/month) or less Every 2 months Every 12 months
When operating
frequency is
great
1,200-times/hr (360,000 times/month) or less Every month Every 6 months
For severe use such as inching, plugging, etc. Determined corresponding to the actual state of use.
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