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Chapter 10 Maintenance
10-2
10.3 Periodic Inspection
Check the following items once or twice every six months, and perform the needed corrective actions.
Check Items
Checking Methods
Judgment
Corrective Actions
Ambient
temperature
0 ~ 55
°
C
Ambient Humidity
5 ~ 95%RH
Ambient
Environment
Ambience
-. Measure with thermometer and
hygrometer
-. measure corrosive gas
There should be no
corrosive gases
Adjust to general standard
(Internal environmental standard of
control section)
Looseness, Ingress
The module should be move
the unit
The module should be
mounted securely.
PLC
Conditions
dust or foreign
material
Visual check
No dust or foreign material
Retighten screws
Loose terminal
screws
Re-tighten screws
Screws should not be loose
Retighten
Distance between
terminals
Visual check
Proper clearance
Correct
Connecting
conditions
Loose connectors
Visual check
Connectors should not be
loose.
Retighten connector mounting
screws
Line voltage check
Measure voltage between input
terminals
*85 ~ 264V AC
*20~28V DC
Change supply power
Fuse
Visual check
No melting disconnection
If fuse melting disconnection,
change the fuse periodically
because a surge current can cause
heat