When The Digital Output Values Cannot Be Read - Mitsubishi Q64AD User Manual

7 TROUBLESHOOTING

7.2.3 When the digital output values cannot be read

Is there any fault with the analog signal lines such as
disconnection?
Is the CPU module in the STOP status?
Are the offset/gain settings correct?
Is the input range setting correct?
Is the A/D conversion enable/disable setting for the channel
that was input set to A/D conversion disabled?
Has the operating condition setting request (Y9) been
executed?
Check item Corrective action
Check for faulty condition of the lines visually and perform a
continuity check of the signal lines.
Set the CPU module to the RUN status.
Verify that the offset/gain settings are correct (see Sections
4.6 and 5.6.2).
If the user range is being used, switch to a different default
input range and check if A/D conversion is correctly
performed. If it is correctly performed, redo the offset/gain
settings.
Check buffer memory addresses 20 and 21 (Un\G20 and
Un\G21) in GPPW system monitor.
If the input range setting is incorrect, redo the GPPW
intelligent function module switch setting (see Section 4.5).
Check the ON/OFF status with buffer memory 0 (Un\G0) in
GPPW system monitor and review the initial setting of the
sequence program or utility package (see Section 3.4).
From GPPW, set the operating condition setting request (Y9)
from ON to OFF, and check that the digital output values are
stored in buffer memory addresses 11 to 18 (Un\G11 to
Un\G18). If so, review the initial setting of the Sequence
program or utility package (see Section 3.3).
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