Siemens SIPART DR21, Manual

Page: 62 / 242

3 Functional description of the structure switches
3.4 Controller types (S1, S42 to S45)
Manual
62
SIPART DR21
C73000-B7476-C143-08
3.4.3 Slave controller, synchronized controller, SPC-controller
with Int/Ext-swtiching (S1 = 1)
SES
w
E
=c4
·
w
e
+c5
w
E
wi
w
ES
x3/w
EA
ya
W
X
W
+
-
X
P I D ya+c6
·
z
0000
z
x1
x=x1+c1 · x2+c3
X
x2
tS
y
y
H
00
wi
Int
∧
CB
Figure 3-7 Control principle S1 = 1
In this controller type you can switch between the internal setpoint wi and the external set-
point w
E
depending on the control signals CB and the Internal-/External key (16) (see
table 3-4, page 65 and table 3-5, page 66).
The external setpoint can be set via the analog input w
EA
or via the SES (w
ES
) (selection by
S85).
This controller type is used for cascade controls with 2 separate controllers (master- and
slave controllers), for synchronized controls, fixed setpoint controls with external setpoint
preset under console conditions with external setpoint generator and SPC-controls (setpoint
control).