Periodic Inspection - Mitsubishi Q172CPU User Manual

6 INSPECTION AND MAINTENANCE

6.3 Periodic Inspection

Item Inspection item
Ambient
temperature
1 Ambient humidity
Atmosphere
2 Power voltage
Looseness, rattling
3
Adhesion of dirt and
foreign matter
Looseness of
terminal screws
Distance between of
4
crimping terminals
Looseness of
connectors
5 Battery
Cooling fan unit
6 (Q173CPU/Q172CPU
only)
The items that must be inspected one or two times every 6 months to 1 year are listed
below. When the equipment is moved or modified, or layout of the wiring is changed,
also implement this inspection.
Table 6.2 Periodic Inspection
Inspection method
Measure with a thermometer
and a hygrometer.
Measure corrosive gas.
Measure a voltage across the
terminals of 100/200VAC and
24VDC.
Move the module to check for
looseness and rattling.
Check visually.
Try to further tighten screws
with a screwdriver.
Check visually.
Check visually.
Preventive maintenance
Check visually.
Criterion
0 to 55 °C (32 to 131 °F)
5 to 95 % RH
No corrosive gases
85 to 132VAC
170 to 264VAC
15.6 to 31.2VDC
The module must be installed
fixedly.
Dirt and foreign matter must
not be present.
Screws must not be loose.
Crimping terminals must be
positioned at proper intervals.
Connectors must not be loose.
No vibration, howl and noise.
(The service life time of the
cooling fan unit: when the
number of the revolution
lower than the 20% of the
initial time. )
6 - 6
Action
If the controller is used in the
control panel, temperature
within the control panel is
equivalent to ambient
temperature.
Change the power supply.
Retighten the screws.
If the CPU, I/O, or power
supply module is loose, fix it
with screws.
Remove and clean.
Further tighten.
Correct.
Retighten the connector
fixing screws.
Even if the lowering of a
battery capacity is not
shown, replace the battery
with a new one if a service
life time of the battery is
exceeded.
Replace it with a new one. If
a service life time of the
cooling fan unit is exceeded,