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9.
TROUBLESHOOTING
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This section describes various procedures for establishing the
nature of any faults, and corrective action.
9.1
Basii
Troubleshooting
System reliability depends not only on reliable equipment but also
on short down-time in the event of faults.
The basic points to be kept in mind in troubleshooting are the
following three.
(1)
Visual checks
Check the following points.
1)
Machine motions
(in
stop and operating statuses)
2)
On or
off
of power
3)
Status of
I/O
devices
4)
Conditions of wiring
(I/O
wires, cables)
5)
Display states of various indicators (such as POWER LED,
6).
States
of
various setting switches (such as extension base
RUN LED, and ERROR LED)
and power failure compensation)
After checking
1)
to
61,
connect the peripheral devices and
check the running status of PC and the contents of program.
(2)
Trouble check
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Observe any changes in the error condition during the
following.
1)
Set the RUN key switch to the "STOP" position.
2)
Perform reset by the RESET key switch.
3)
Turn the power on and
off.
(3)
Narrow down the possible causes of the trouble
Deduce where the fault lies
i.e:
1)
Inside or outside of
PC.
2)
I/O
modules or other modules.
3)
Sequence program.
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