Siemens SIPART DR21 User Manual

6 Commissioning
6.1 Adapting the direction of control action to the controlled system
Manual
SIPART DR21
C73000-B7476-C143-08
181
6 Commissioning
6.1 Adapting the direction of control action to the controlled
system
D Definitions
Normal control action system
Rising y causes rising x; e.g. an increasing energy supply or mass flow causes a rising
temperature.
Normal effecting actuator (valve):
Increasing current or positioning command +y cause the actuating element (increasing y)
to open, e.g. more energy or greater mass flow. y
displ.
is the displayed manipulated variable.
The direction of control action is referred to the controlled variable x1. The following state-
ments apply for transmitters with normal control action (increasing physical variable causes
increasing transmitter current), increasing process display (dE > dA) and no falling charac-
teristic in the linearizers.
D Direction of control action of system and final control element known
K-controller
The following is prescribed: Select the desired control action here:
T
h
i
s
g
i
v
e
s
t
h
e
s
e
t
t
i
n
g
s
o
f
S
4
6
Direc-
tion of
c
o
n
t
r
o
l
Direc-
tion of
c
o
n
t
r
o
l
Direc-
tion of
c
o
n
t
r
o
l
2
0
m
A
pressing the right key
causes in manual operation
T
h
i
sg
i
ves
t
h
ese
t
t
i
ngs o
f
S
4
6
and S55 and the mode of oper-
ation of the controller
control
action
of the
system
control
action
of the
actuator
control
action
of the
system
and the
actuator
20 m
A
on
actuat-
ing cur-
rent ly
valve Actual
value/
con-
trolled
variable
S46 Kp
(cP)
S55
y
displ.
=
l
normal normal 100 % rises opens rises 0 pos. 0 y
normal
revers-
ing
revers-
ing
0% falls opens rises 1 neg. 1 100 % -y
n
o
r
m
a
l
r
e
v
e
r
s
-
0% falls closes rises 1 neg. 1 100 % -y
revers-
i
norma
l
revers-
ing
100 % rises opens falls 1 neg. 0 y
r
e
v
e
r
s
ing
revers-
i
normal 100 % rises closes rises 0 pos. 0 y
ing
0% falls opens falls 0 pos. 1 100 % -y
Two more lines could be added to the table which are useless in practice: normal action system in which the actual values
falls with a rising change in the manipulated variable.
Table 6-1 Direction of control action and y-display direction of control action of the system- and final
control element direction of control action in K-controllers

Siemens SIPART DR21 Specifications

General

Brand	Siemens
Model	SIPART DR21
Category	Controller
Language	English