45
4 - Operation
4.5.3 PID MENU
Not present with On-Off main
output.
Proportional
Band
Cool Proportional
Band
This parameter specifies the pro-
portional band coefficient that
multiplies the error (SP - PV)
Integral
Time
Cool integral
Time
It is the integral time value, that
specifies the time required by the
integral term to generate an output
equivalent to the proportional term.
When Off the integral term is not
included in the control algorithm.
#t.i. C
#t.i.
#p.b. C
#p.b.
Derivative
Time
Cool Derivative
Time
It is the time required by the pro-
portional term P to reach the level of
D. When Off it is not included.
Overshoot
control
(Automatically disabled when the
adaptive tune is running)
This parameter specifies the
span of action of the overshoot
control. Setting lower values
(1.00—>0.01) the overshoot
generated by a Setpoint change
is reduced. The overshoot con-
trol doesn’t affect the effective-
ness of the PID algorithm.
Setting 1, the overshoot control
is disabled.
#O.C.
#t.d. C
#t.d.
Manual
reset
This term specifies the value of
the control output when PV = SP,
in a PD only algorithm (lack of
the Integral term).
Error
Dead Band
Inside this band for (PV - SP), the con-
trol output does not change to pro-
tect the actuator (output Stand-by)
#d.err
#M.res
4.5.4 TUNING MENU
(not shown for ON-OFF
main control output)
See page also 57
Two tuning method are provided:
• Initial one shot Fuzzy-Tuning
• Continuous, self learning
Adaptive Tuning
The Fuzzy-Tuning determines
automatically the best PID term with
respect to the process behaviour.
The controller provides 2 types of
“one shot” tuning algorithm, that
are selected automatically accord-
ing to the process condition when
the operation is started.
STEP response
SP
End of the tuning
operating and
setting of the new
calculated terms
Start of autotune
operation
Setpoint change
PV variable
Control output
x5-uk-ed5 17-09-2009 14:53 Pagina 45
To Next Page
Loading...
Need help?
General
