user manual

Configuration
January 2009 UDA2182 Universal Dual Analyzer Product Manual 97
Table 6-14 PID Tuning
Sub-menu
selection
Parameter Selection or
Range of Setting
Parameter Definition
Accutune Enable
Disable (default)
When enabled, the analyzer will start
controlling to the setpoint while it identifies the
process and adjusts the Gain or Proportional
Band (P), Rate (I), and Reset Time (D) tuning
constants in response to setpoint changes
and/or Process Variable disturbances.
Fuzzy Logic Enable
Disable (default)
Fuzzy Overshoot Suppression minimizes
overshoot after a setpoint change or a process
disturbance.
The fuzzy logic observes the speed and
direction of the PV signal as it approaches the
setpoint and temporarily modifies the internal
control response action as necessary to avoid
an overshoot.
There is no change to the PID algorithm, and
the fuzzy logic does not alter the PID tuning
parameters.
This feature can be independently Enabled or
Disabled as required by the application to work
with Accutune.
Use Prop Band Enable
Disable (default)
When enabled, Proportional band is used
instead of Gain (default).
See “Gain or Prop Band”.
Use RPM Enable
Disable (default)
When enabled, Repeat per minute is used
instead of Minutes per Repeat (default).
See “Reset”.
Gain or Prop Band Gain – 0.1% to
1000.0%
PB – 0.1 to
1000.0%
default = 1.000
Gain (default) – is the ratio of output change
(%) over the measured variable change (%)
that caused it.
G =
100 %
PB %
where Prop Band is the proportional Band (in
%of Input Range)
Proportional Band (Prop Band) - is the
percentage of the range of the measured
variable for which a proportional controller will
produce a 100 % change in its output.
PID 1 Tune
PID 2 Tune
Rate -0.035 to 10.000
default = 0.000
RATE action, in minutes affects the control
output whenever the deviation is changing; and
affects it more when the deviation is changing
faster. The amount of corrective action
depends on the value of Gain.