Mitsubishi Electric MELSEC-Q Series User Manual page 46

3 SPECIFICATIONS
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REMARKS
1) The time required for auto tuning differs depending on the control-target device.
2) The completion of auto tuning can be checked with the status change (on to off)
of Auto turning status flag (Xn4, Xn5).
3) When Automatic backup setting after auto tuning of PID constants (buffer
memory address: 63, 95) is set to enabled in advance at the start of auto tuning,
the PID constants and loop disconnection detection judgment time are
automatically stored in FeRAM at completion of auto tuning.
4) If the auto tuning does not complete after long period, take any of the corrective
actions below.
(a) When the measured value (PV) does not change properly
1) Check if load and external operation device are properly connected. If not,
connect them properly and then perform the auto tuning.
2) If using in the reverse action, check whether the set value is set not to
change the manipulated vale. If so, set the set value in the value to
control and perform the auto tuning.
(b) When the measured value (PV) changes properly
1) If the response of the control target is slow, wait until the completion of the
auto tuning.
5) If the PID constants have not changed after the completion of the auto tuning,
check if the PID constants are constantly written using the sequence program.
If written, delete the sequence program of corresponding parts.
MELSEC-Q
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