-17-
Released 2018-01-12
Drawing No. LP0932
0.0
OPOF
OUTPUT POWER OFFSET
When the Integral Time is set to zero, the power offset is used to shift
the proportional band to compensate for errors in the steady state. If
Integral Action is later invoked, the controller will re-calculate the internal
integral value to provide “bumpless” transfer and Output Power Offset
will not be necessary.
-100.0
to
100.0
% power
0
ProP
PROPORTIONAL BAND
1
to
9999
display units
The Proportional Band, entered as process units, is the amount of
Process Value change required to vary the output full scale. The
Proportional Band is adjustable from1 to 9999, and should be set to a
value that provides the best response to a process disturbance while
minimizing overshoot. A Proportional Band of 0 forces the controller into
On/Off Control with its characteristic cycling at setpoint. The optimal
value may be established by invoking Auto-tune.
120
In
INTEGRAL TIME
0
to
9999
seconds
Integral action shifts the center point position of the proportional band
to eliminate error in the steady state. The higher the integral time, the
slower the response. The optimal integral time is best determined during
PID Tuning.
30
dr
DERIVATIVE TIME
0
to
9999
seconds
Derivative time helps to stabilize the response, but too high of a
derivative time, coupled with noisy signal processes, may cause the
0.0
dIn
INTEGRATION DEFAULT
0.0
to
100.0
% output power
The Integration Default is the default integration value of integral
control. When the process value enters the proportional band, the PXU
will take the Integration Default as the default control output of integral
control. The value is determined at Auto-Tune.
NO
N
AUTO-TUNE START
NO
Y
The Auto-Tune procedure sets the Proportional Band, Integral Time,
Derivative Time, Integration Default, and relative Gain (Heat/Cool)
values appropriate to the characteristics of the process. This parameter
allows front panel starting
Y
or stopping
NO
of Auto-Tune. For more
information, see PID Tuning Explanations.
P-1
PL
SETPOINT SELECT
P-1
or
P-2
The Setpoint Select parameter is available only when operating in
Setpoint Control mode (
P
=
P
). The
PL
function allows the operator
to select setpoint 1 or setpoint 2 as the active setpoint value.
ALARM RESET
This parameter provides for the ability to individually reset active
alarms from the front panel, without using
1
or
2
function keys. When
ALr
is displayed with
1-2
on bottom display, pressing the
B
key, under
the 1, will reset an active Alarm 1. Pressing the
J
key, under the 2, will
reset an active Alarm 2. When
ALr
is displayed with 3 on the bottom
display, pressing the
J
key, under the 3, will reset an active Alarm 3. All
alarms may be simultaneously reset from the front panel by using User
1
or
2
programmed for
ALr
.
1-2
3
1-2
ALr
PId
CRL
AUTO CONTROL MODE
PId
or
OnOF
Select the desired control mode. When
OnOF
is selected, the PID
parameters are not available.
0
ProF
STARTING PROFILE
0-9
and
A-F
The Starting Profile parameter sets the profile that will start and run
when the Controller status,
r-
is set to run, or powered up with
Controller status of run.
0
Pg
STARTING PROFILE SEGMENT
0-9
and
A-F
The Starting Profile Segment is the first profile segment that the
profile will start running when the Controller status,
r-
is set to run.
0.0
r-i
PROFILE TIME
0
to
999.9
This Line 2 parameter displays the remaining segment time in
tenth of a minute resolution.
100.0
AL-x
ALARM VALUE
The alarm values are entered as process units or degrees. When the
alarm is configured as deviation or band acting, the value entered is the
offset or difference from the setpoint at which the alarm condition occurs.
0
to
9999
output to fluctuate too greatly, yielding poor control. Setting the time to
zero disables derivative action. The optimal Derivative Time is best
determined during PID Tuning.
