4. Press and hold until appears on the display.
5. Press for at least 3 seconds. The AT indicator will begin to
flash and the auto-tuning procedure is beginning.
3 -11 Auto-tuning
The auto-tuning process is performed at set point.
The process will oscillate around the set point during tuning
process. Set
the
set
-
point to a lower value if overshooting
beyond the normal process value is likely to cause damage.
The auto-tuning is applied in cases of :
Initial setup for a new process
The set point is changed substantially from the previous auto-
tuning value
The control result is unsatisfactory
*
*
*
Operation :
1. The
unit
has been installed normally.
2. Set the correct values for the setup menu of the unit.
But don't use a zero value for PB and TI , otherwise, the
auto-tuning program will be disabled. The LOCK parameter
should be set at NONE.
3. Set the set point to a normal operating value or a lower value if
overshooting beyond the normal process value is likely to
cause damage.
NOTE :
The ramping function, if used, will be disabled once auto-tuning
is proceeding.
The auto-tuning mode is disabled as soon as either failure mode
or manual control mode occurs.
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