ascon G2 Series User Manual

25
4 - Operation
4.3.1 PARAMETERS (cont.)
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—>0.01) the
overshoot generated by a Setpoint
change is reduced. The overshoot
control doesn’t affect the effective-
ness of the PID algorithm.
Setting 1, the overshoot control is disabled.
Manual
reset
This term specifies the value of the
control output when PV = SP, in a PD
only algorithm (lack of the Integral
term).
TUNING
Two tuning method are provided:
• Initial one shoot Autotuning
• Continuous, self learning Adaptive
Tuning
When the Autotuning is started, the
controller generates a rapid burst of
ON - OFF transition and monitors the
response, in order to calculate the
optimal PID terms parameters. Once
calculated the terms values are imme-
diately used in the control algorithm.
(a minimun error of 5% of span is
needed to start the Autotuning)
#M.res
#O.C.
INPUT MENU
Input filter
Time constant, in seconds, of the RC
input filter on the PV input. When this
parameter is Off the filter is
bypassed.
Measure
Bias
This value is added to the measured
PV input value. Its effect is to shift the
whole PV scale of its value (±60 dig-
its).
Sampling
Time
Sampling time, in seconds, of the
instrument. This parameter is normally
used when controlling slow process,
increasing the sampling time from 0.1
to 10 seconds.
#t.saM.
#In.sh
Filter reponse
100%
0
PV
63,2%
Filter
Time
Time
#t.fil
The self-learning adaptive autotune,
is not intrusive. It doesn’t affect the
process, at all, during the phase of
calculation of the optimal terms para-
meters.
It is particularly suitable for con-
trolling process whose control
characteristics change with time
or are not linear in relation to the
Setpoint values.
It doesn’t require any operation by the
user. It is simple and works fine: it
samples continuously the process
response to the various perturbations,
determining the frequency and the
amplitude of the signals. On the basis
of this data and their statistical val-
ues, stored in the instrument, it mod-
ifies automatically the PID term para-
meters.
It is the ideal for all applications where
it is required to change continuous-
ly the PID terms parameters, in order
to adjust the PID to the changes of
the process dynamic conditions.
One shot initial autotuning
SP
End of the tuning
operation and start
of control with the
new terms values
Autotune start
Setpoint
change
PV variable
Control
output
In case of power off with the
Adaptive Tune enabled, the values
of the PID terms parameters are
stored, in order to be reused at the
next power on.
At power on the Adaptive Tune
starts automatically.
Perturbation
New
parameters
Continuous adaptive tune
M5 UK•ed4 10-12-2004 16:20 Pagina 25

ascon G2 Series Specifications

General

Brand	ascon
Model	G2 Series
Category	Controller
Language	English