i
AUTO TUNING MODE :
To enter in this mode, Press & hold SHIFT key for minimum 3 sec.
PARA
METER
DESCRIPTION
DEFAULT
This function will be executed only if selected control action is PID.
Auto-tuning function can be initiated by setting this parameter to ‘YES’. The decimal of LSB
flashes till Auto Tuning function is in progress. During Auto-tuning, Controller learns the process
characteristics by itself & calculates required P, I & D values.
User can cancel or abort this feature by setting this parameter to ‘NO’.
AUTO
TUNING
MODE
NO
DISPLAY
5
OIM AI-7X41 V2.1 Page 5 of 5
338, New Sonal Link Service Industrial Premises Co-op Society Ltd,
Building No.2, Link Road, Malad (W), Mumbai - 400064.
Tel: 022-66939916/17/18;
E-mail : sales@itherm.co.in
Website : www.itherm.co.in
Mfgd by: Innovative Instruments & Controls LLP
i
15
Default USER LOCK CODE is 15 to access Control & Configuration List.
User has a choice to set its own USER LOCK CODE between 1 to 9999, this is to prevent
unauthorized access of Control & Configuration List.
USER
LOCK
CODE
SET
POINT 1
ENABLE
If Enabled, User can View & edit the Set point 1 in USER list.
If disabled, User can only View the Set Point 1 but Can not edit it in USER list.
AUTO
TUNE
ENABLE
If Enabled, this parameter will be prompted if user press Up & Down keys Simultaneously for
3Sec.
If Disabled, this parameter will not be prompted if user press Up & Down keys Simultaneously
for 3Sec.
PARA
METER
DESCRIPTION
DEFAULT
DISPLAY
ON-OFF ACTION :
In this mode, Output (Relay/SSR) remains ON till actual temperature reaches to the set point value. On
reaching SP, Output turns OFF & remains OFF till actual temperature drops down (in Heat logic) or raises (in Cool logic) equal to
hysterisis set by User. (As shown in Fig : 3.1 & 3.2)
Fig: 3.1
HEAT LOGIC / ON-OFF
TIME
0
TEMP ( C)
HYSTERISIS
SP
ON
ON
ON
AMB
O/P
OFF
OFF
Fig: 3.2
TIME
COOL LOGIC / ON OFF
O/P
O/P
0
TEMP ( C)
AMB
HYSTERISIS
ON
ON
ON
SP
OFF
OFF
USER GUIDE
:
AUTO TUNING MODE :
In this mode, Controller learns the process characteristics by itself and calculates the required P,I &
D values. It can be performed at any time after power ON but, it is best to start it when the process is at Ambient temperature in order
to minimize overshoot & undershoot. Auto tuning is applied in case of :
(1) Initial set up for a new process.
(2) Substantial change in SP from previous auto tuning value.
(3) Control accuracy is not satisfactory.
If the control performance by using auto-tuning is still unsatisfactory, User can apply the further adjustments of P,I & D values as shown
below
Adjust
Proportional Band
Integral Time
Derivative Time
Slow Response
Over Shoot or Oscillations
Slow Response
Instability or Oscillation
Slow Response or Oscillation
High Over Shoot
Decrease PB
Increase PB
Decrease Int
Increase Int
Decrease Dt
Increase Dt
Symptom
Solution