When An Analog Output Value Is Not Output - Mitsubishi Electric Q62DAN User Manual

8 TROUBLESHOOTING

8.2.3 When an analog output value is not output

Check item
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 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 Operating condition setting request (Y9)
been executed?
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Verify that 24VDC voltage is being supplied to the external power
supply terminals
(Q62DAN, Q64DAN, Q62DA, Q64DA: terminal numbers 16, 17
Q68DAVN, Q68DAIN, 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 (Refer to sections 4.6,
5.6.2 and 5.6.3).
If the user range setting is being used, switch to a different default
output range and check if D/A conversion is correctly performed. If it
is correctly performed, redo the offset/gain settings.
Verify setting range (buffer memory addresses 20, 21 (Un\G20,
Un\G21) in GX Developer monitor. If the output range setting is
incorrect, redo GX Developer intelligent function module switch
settings (Refer to Section 4.5).
Check the on/off status of 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. (Refer to Section 4.5.)
Check the setting of D/A conversion enable/disable (buffer memory
address 0: Un\G0) in GX Developer monitor and set it to Enable using
the sequence program or utility package (Refer to Section 3.4).
Verify on/off for CH
Developer monitor.
If the output enable/disable flags are off, review the initial setting for
the sequence program or utility package (Refer to Section 3.3).
Verify CH
in GX Developer monitor (Refer to Section 3.4).
Set 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 (Refer to Section 3.3).
POINT
If the analog output value is not output after the proper corrective action is taken in
accordance with the above check item, the possible cause is a module failure.
Consult the nearest sales representative or branch.
Action to be taken
Output enable/disable flag (Y1 to Y8) in GX
Digital value (buffer memory address 1 to 8 (Un\G1 to 8)
MELSEC-Q
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