Siemens LOGO! Manual page 168

LOGO! functions
4.4 Special functions list - SF
Example
In a heating control system, the supply T
compared, for example with a sensor at AI2.
A control signal is to be triggered (for example "heater On") when the difference between the
supply and return line temperatures is greater than 15 °C. The control signal is reset when
the difference is less than 5 °C.
The process variable of the temperature is to be shown in parameter assignment mode.
The thermocouples available have the following technical data: -30 to +70 °C, 0 to 10 VDC.
Application
-30 to +70 °C = 0 to 10 V DC
0 °C
Range of values:
-30 to +70 °C = 100
On threshold = 15 °C
Off threshold = 5 °C
See also topic "Calculating the gain and offset of analog values (Page 117) ".
Configuration (example):
Press
168
and return line temperatures T
v
Internal mapping
0 to 1000
300
→ Offset = -30
1000
→ Gain = 100/1000 = 0.1
Threshold = 15
Threshold = 5
are to be
r
Manual, 10/2017, A5E01248535-AA
LOGO!