Siemens SIPART DR22 Manual page 55

Manual
the control signal CB and the Internal/External key:
DDC operation ≙ RC=Int∧CB = 1
0000
wi
x-TRACKING
x1
FE1
x2
x=x1+c1 · (x2-c2·x3+c3)
FE2
x3
FE3
z
FE4
y
N
FE5
Figure 1-28 Principle representation S1 = 2
The DDC mode is signaled like the follow-up mode in the other controller types by the lit y-Ex-
ternal LED. The status of the control signal CB and the Internal/External key is displayed by the
LEDs C and Internal. During the DDC mode the setpoint is prepared by follow-up to the com-
puter failure. The setpoint is always displayed which would become active after the computer
failure.
With S50 a choice is made between x-tracking and wi, with S51 the safety setpoint is preset.
With S61 the priority between DDC-mode and manual mode is determined. If DDC-mode has
priority over manual mode, you can select with the manual-automatic switching whether opera-
tion is to continue after a computer failure in automatic or manual mode. If manual intervention
is necessary in computer operation, switching to Internal operation is necessary in addition to
switching to manual operation; the LEDs Internal (1) and Manual (8) light, the LED y-External
(10) goes out, the dark LED C (3) stil indicates computer standby.
If manual mode has priority over DDC-mode you can switch directly from computer operation to
manual operation. Then the manual LED (8) lights, the y-External LED (10) goes out, the dark
LEDs Internal (1) and C (3) still indicate computer standby of the controller or computer
standby.
Automatic mode is always switched to here in the event of a computer failure.
SIPART DR22 6DR2210
C79000-G7476-C154-03
0000
x
w
tS
W
+
--
x
1.5 Functional description of the structure switches
1.5.4 Controller types (S1, S49 to S53)
y
H
y +c6 · z
P I D
a
y
a
1 Technical Description
000
Y
INT∧CB
y
N
YES
SES
53