When An Analog Output Value Is Not Output - Mitsubishi Q62DA User Manual

7 TROUBLESHOOTING

7.2.3 When an analog output value is not output

Is 24VDC external power supply being supplied?
Is there any fault with the analog signal lines such as broken
or disconnected line?
Is the CPU module in the STOP status?
Are the offset/gain settings correct?
Is the output setting range correct?
Is the resolution mode setting correct?
Is the D/A conversion enable/disable setting for the channel
to be output set to Disable?
Is the D/A output enable/disable setting for the channel to be
output set to Disable?
Is the digital value being written to the channel to be output?
Has the operating condition setting request (Y9) been
executed?
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Check item Action to be taken
Verify that 24VDC voltage is being supplied to the external
power supply terminals
(Q62DA, Q64DA: terminal numbers 16, 17
Q68DAV, Q68DAI: terminal numbers 17, 18).
Check for any abnormality on the signal lines by doing a
visual check and performing a continuity check.
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 setting is being used, switch to a different
default input range and check if D/A conversion is correctly
performed. If it is correctly performed, redo the offset/gain
settings.
Verify buffer memory address 20 and 21 (Un\G20 and
Un\G21) in GX Developer monitor. If the output range setting
is incorrect, redo GX Developer intelligent function module
switch settings (see Section 4.5).
Check the ON/OFF status of the high resolution mode status
flag (X8) in GX Developer system monitor.
If the resolution mode setting is incorrect, redo the GX
Developer intelligent function module switch setting. (See
Section 4.5.)
Check the D/A conversion enable/disable setting using
buffer memory 0 (Un\G0) in GX Developer monitor and set it
to Enable using the sequence program or utility package
(see Section 3.4).
Verify ON/OFF for the output enable/disable flags (Y1 to Y8)
in GX Developer monitor.
If the output enable/disable flags are OFF, review the initial
setting for the sequence program or utility package (see
Section 3.3).
Verify buffer memory addresses 1 to 8 (Un\G1 to Un\G8) in
GX Developer monitor (see Section 3.4).
Set the operating condition setting request (Y9) from ON to
OFF from GX Developer and check to see if the analog
output is normal.
If normal analog output is obtained, review the initial setting
for the sequence program or utility package (see Section
3.3).
MELSEC-Q
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