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LOGO! Manual
A5E00067781 01
Example
To control a heating system, the flow temperature T
v
(via a
sensor at AI1) and the return temperature T
r
(via a sensor
at AI2) are to be compared with each other.
If the return temperature differs by more than 15 C from
the flow temperature, a switching operation is to be trig-
gered (e.g. burner on).
The real temperatures are to be displayed in PARAM
mode.
Temperature sensors with the following technical specifica-
tions are available: –30 to +70 C, 0 to 10V DC.
Application Internal Representation
–30 to +70 C = 0 to 10V DC 0 to 1000
0 C 300
Offset = –300
Value range:
–30 to +70 C = 100
1000
Gain = 100/1000
= 0.1 = 10 %
Switching threshold = 15 C Threshold value = 15
Parameter assignment
B03:Par
=00015
=0010+
=-300
Display in PARAM mode (examples):
B03:Par
=20
Ax = 10
Ay = 30
B03:Par
=30
Ax=10
Ay =– 20
LOGO! Functions
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