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2.3.3 Auto Tuning
When AI control method is chosen (CtrL=APId / nPId), the PID parameters can be obtained by
running auto-tuning.
In basal display status, press
for 2 seconds, the
“
At
”
parameter will appear.Press
to
change the value of
“
At
”
from
“
oFF
”
to
“
on
”
,then press
to active the auto-tuning
process.During auto tuning,the instrument executes on-off control.After 2-3 times of on-off
action,the instrument will obtain the optimal control parameter
value.
If you want to escape from auto tuning status, press and hold the key for about 2 seconds until the
"At" parameter appear again. Change
“
At
”
from
“
on
”
to
“
oFF
”
, press to confirm, then the
auto tuning processwill be cancelled. (P.S. If parameter
“
SPr
”
activate and the heating was
running, then will stop the
“
At
”
until completed the heat up process. ) If the controller was applied
on heat/cooling duel output system, PID parameter need separate two group to process auto tuning.
When the controller was cooling control from AUX, this time can enable auto tuning to obtain P2, I2,
d2.
Note 1:
At AI-516P, when auto tuning was running, the program timer will stop until tuning finish.
Note 2:
If the setpoint is different, the parameters obtained from auto-tuning are possible different. So you
’
d better set setpoint to an often-used value or middle value first, and then start auto-tuning. For the
ovens with good heat preservation, the setpoint can be set at the highest applicable temperature.
Depending on the system, the auto-tuning time can be from several seconds to several hours.
Note 3:
Parameter CHYS (on-off differential, control hysteresis) has influence on the accuracy of
auto-tuning. Generally, smaller value of CHYS, will get higher precision of auto tuning result. Too
large value of CHYS, will made the controller out of control, so, CHYS is recommended to be 2.0.
Note 4:
AI series instrument has the function of self-adaptation. It is able to learn the process while working.
He control effect at the first run after auto tuning is probably not perfect, but excellent control result
will be obtained after a period of time because of self-adaptation.
3. PARAMETERS AND SETTINGS
3.1 Parameter Lock (Loc) and Field Parameters
Parameter was protected by LOC (Parameter LOCK) to prevent setting error. The function was
shown as below:
√
: allow to modify data or execute
X : not allow to modify data or execute
Run, Stop, Hold. and Program Time & Temp. function just for AI-516P only
