User`s manual

Maintenance and inspection Periodic inspection
10 – 2
10.2 Periodic inspection
The items that must be inspected one or two times every 6 months to 1 year are listed below.
When the equipment has been relocated or modified, or wiring layout has been changed, per-
form this inspection.
Inspection item Inspection Judgment criteria Measures
Ambient
environment
Ambient
temperature
Measure with a ther-
mometer and a hygrom-
eter. Measure corrosive
gas.
0 to 55 °C When the sequencer is
used in the board, the
ambient temperature in
the board is relevant.
Ambient
humidity
5 to 95 % RH
Atmosphere Corrosive gas must not be
present.
Power voltage Measure the voltage
between the terminals
(power supply module)
85 to 132 V AC
170 to 264 V AC
15.6 to 31.2 V DC
Change the power sup-
ply or replace the trans-
former
Installation
of modules
Looseness,
rattling
Move the module to
check for looseness and
rattling.
The module must be installed
securely.
Retighten the screws. If
the CPU, I/O, or power
supply module is loose,
fix it with screws.
Adhesion of
dirt and for-
eign matter
Check visually. Dirt and foreign matter must
not be present.
Remove and clean.
Connections Looseness
of terminal
screws
Check for loose terminal
screws.
Screws must not be loose. Retighten the terminal
screws.
Proximity of
solderless
terminals to
each other
Check visually. Solderless terminals must be
positioned at proper intervals.
Correct.
Looseness
of connec-
tors
Check visually. Connectors must not be loose. Retighten the connector
fixing screws.
Battery Check the BAT. LED at
the front side of the CPU
module.
The LED must be off. Replace the battery
when the BAT. LED is
on.
Check the length of term
after purchasing the bat-
tery.
Must not be used more than 5
years.
Replace the battery if it
has been used more
than 5 years (even if
there is no voltage drop).
Check status of SM51
and SM52
Must be turned off (refer to sec-
tion 10.3.1)
Replace the battery
when SM51 or SM52 is
on.
The special registers
SD51 and SD52 indi-
cate the specific battery
of the memory of which
voltage is lowered.
PLC diagnostics Check the Error log. The Error log must not be
updated.
refer to section 11.3
Maximum scan time Check the values of
SD526 and SD527 using
a programming device
Maximum scan time must be
within the allowable range
given in the specification of the
system.
Specify factors that
increase the scan time.
(Check the operation
status of the trigger sig-
nal that passes through
a loop if loop positions
exist in the sequence
program.)
Tab. 10-2: Periodic inspection