Siemens S5-100U User Manual page 291

S5-100U
11.6.2 Output of Analog Value - FB251 -
Analog values can be output to analog output modules using this function block. In doing so, values
from the range between the lower limit (UGR) and high limit (OGR) parameters are converted to the
nominal range of the module in question.
Table 11-18.
Parameter
XE
BG
KNKT
OGR Upper limit of the output
UGR Lower limit of the output
FEH
BU Input value exceeds
Example: Display of Tank Contents on an Analog Measuring Instrument
The make-up quantity of a 30 m
FB250). The ± 20 mA analog output module in slot 1, channel 0, transfers the standardized value
to the measuring instrument. The value is displayed within the range 0 to 20 mA.
PS CPU
Figure 11-14. Schematic for "Display of Tank Contents"
EWA 4NEB 812 6120-02
Call and Parameter Assignments of FB251
Explanation
Analog value to be
output
Slot address
Channel number
Channel type
value
value
Error in limit value
setting
UGR or OGR
3
tank is stored in flag word 1 as a fixed-point number (see example
AQ
Type Assignment
I W Input value (two's
complement) in the
range UGR to OGR
D KF 0 to 7
D KY KY = x,y
x = 0;1
y = 0;1
0: unipolar repre-
sentation
1: bipolar fixed-point
number
D KF -32767 to +32767
D KF -32767 to +32767
Q BI "1" if UGR = OGR,
invalid channel or slot,
or invalid channel type
Q BI "1" if XE lies outside
limits (UGR; OGR).
XE assumes the limit
value
Analog Value Processing
: JU FB 251
NAME : RLG:AQ
XE :
BG :
KNKT :
OGR :
UGR :
FEH :
BU :
11-25