Pd - Pd Controller - Siemens Moore 353 User Manual

UM353-1

3.2.77 PD - PD Controller

PD is a proportional only controller with manual reset. It is
one of five controller types that can be used on a one per
loop basis.
Manual reset allows the output of the controller to be set
for a normal operating value (i.e. the desired output when
the process equals setpoint under a given load condition).
Derivative action is provided when the parameter TD is
non-zero. The controller includes an autotune feature that
can be initiated from the operator faceplate using the quick
TUNE feature.
When input A is high (1) the controller will operate in the
normal auto mode and when low (0) causes the controller
output to track the feedback signal to eliminate bumping
the output when switching to auto. This is accomplished by
forcing the reset component R to a value that will keep
(GE+R) equal to the feedback value. When the controller
is switched to auto the value of the reset component will
change back to the manual reset MR value at a rate
determined by the MR TLAG setting. When MRTRCK is
set to YES the manual reset MR will also track the
feedback signal when input A is low.
Input I, when changed from low (0) to high (1) or high to
low, will cause the controller to initialize (i.e. eliminate
any proportional gain action during that scan cycle). This
can be used to prevent bumping the output when changes
are made to the setpoint through a switch block.
Process
Engineering
P
INput units
scaling
t
t
D
DG
Lead
+
-
Engineering
S
INput units
scaling
.
Setpoint
Absolute Value
March 2003
PD Controller
+
D S
+
+ 1
S
+
e
A PG
-
1
-
+/
RanGe PoinTeR
Absolute Error
BLOCK DIAGRAM
AE
PD CONTROLLER
PD ESN = 000
R
Range
P
Process
PD
Setpoint S
CONTROLLER
F
Feedback
A
Auto
I
Initialize
R G P T R RanGe PoinTeR
D I R A C T
DIRect ACTing
P G
Proportional Gain
T D Time - Derivative
D G
Derivative Gain
M R
Manual Reset
(S)
M R T L A G
Manual Reset Time LAG
M R T R C K
Manual Rest TRACKing
M I N S C A L E
MINimum SCALE
M A X S C A L E
MAXimum SCALE
D P P D P P
ecimal oint osition (preferred)
E N G U N I T S
ENGineering UNITS
A U T O T U N E
AUTOTUNE
(S)
% D E V % DEViation
during Autotune
% H Y S
% HYSteresis during Autotune
% S T E P
% STEP
output on first Autotune
A T D Y N A M
AT DYNAMic settings
A T R E S E T .................................... NO/YES
AT RESET
(S)
P O S T A T
POST Autotune Transfer
I N P U T
P INPUT P .......................
(H)
I N P U T S INPUT S .......................
(H)
I N P T F .......................
U INPUT F
(H)
I N P U A
T INPUT A ......................
(H)
I N P U T I INPUT I ........................
(H)
E S N
Exec. Seq. No.
ENG UNITS
+
Limit
-3.3 < O < 103.3%
+
Lag
R
1
T
MR
t
+ 1
S
M R
Auto
Initialize
Function Blocks
OR
Output Range
O1
Output
AE Absolute Error
AW AT Warning
....................
loop tag.block tag (null)
(S)
................................ NO/YES
(H) (NO)
................... 0.001 to 100.0
(1.000)
(S)
............. 0.00 to 100.00 min
(0.00)
(S)
........................ 1.00 to 30.00
(S) (10.00)
......................... 0.00 to 100.00
(0.00)
. 0.001 to 4000 min
(0.010)
(S)
.................. NO/YES
(S) (NO)
.................................. Real
(H) (0.0)
................................. Real
(H) (100.0)
(S) ........... 0.0.0.0.0.0 (0.0)
.................6 ASCII Char
(S) (PRCT)
................................... NO/YES
(YES)
.... AUTO, 2.5 to 25.0 (AUTO)
(S)
.. AUTO, 0.5 to 10.0 (AUTO)
(S)
(S) ............ 5% to 40% (10)
.... Fast, Medium, Slow
(M)
(S)
(YES)
................ NO/YES
(S) (NO)
loop tag.block tag.output (null)
loop tag.block tag.output (null)
loop tag.block tag.output
(null)
loop tag.block tag.output (null)
loop tag.block tag.output (null)
............................. 001 to 250
(H)
scaling
O1
Output
inverse scaling
F
Feedback
A
.
I
3-81