Auto Tune
(Limit Cycle Tuning) operation ;
if heating or heating-cooling function and PID control form is selected, process
control output runs according to heating
if cooling function and PID control form is selected, process control output runs
according to cooling .
44
Self Tune ( Step Response Tuning ) :
When power is on, while process value starts to change for being equal to process
set value, PID parameters are determined by the device with
Self Tune
method.
For starting
Self Tune ( Step Response Tuning )
operation firstly power off and
then apply power to the device. Also difference between process value and set
value must be too much.
i
PID coefficients were determined
Process
Value
Time
While Atun
operation
100%
Process
Output
Control is unstable
Process Set
Value ( )
Example 2 : Determination of PID parameters with Self Tune method
!
Enter technician menu
Select tune selection parameter in “run List” menu or
and turn to operation screen.
Power off the device.
Wait system to be in first conditions.
(For example : Decrease of the temperature to ambient temperature while
controlling the temperature)
Apply power to the device
See that “AT” led is active
!
!
!
!
!
If heating or heating-cooling function and PID control form is selected for the
system;
If set value is greater than process value, process output becomes active till to the
Temp[(Set - Temperature) / 2]
value. When process value reaches to this
value, process output reduces to 0% and it calculates the PID coefficients.
For Self Tune ( Step Response Tuning ) operation
:
1 - Tune selection parameter in “run List” menu must be selected
Self tune
Or
Auto-Self Tune
2 - For
Self Tune ( Step Response Tuning )
operation, firstly power off and then
apply power to the device.
3 -
For being started Tune operation (Auto Tune or Self Tune) control form must be P,
PI, PD or PID.
4 -
If process set value is changed while Tune operation is being performed, Tune
operation is canceled.