Cooling circuit
Heating circuit
Controller output
Controller output
Process Variable
Controller
Set point
For this application, two controllers must be configured: one with direct output for the heating pump and one with inverse output for
the cooling pump. To achieve the illustrated inverse output, an offset of 100 % is needed. See the sections about “Analogue offset”
and “Example of inverse output with 100 % offset” for more information regarding offset.
Temperatures below 20 °C then result in a positive output for the heating pump, in the same way as temperatures above 20 °C
result in a positive output for the cooling pump, and the temperature is maintained around the set point.
Set point
40 °C
20 °C
0 °C
Output
100 %
0 %
Direct output
(Heating)
Inverse output
(Cooling)
Time
8: Analogue offset
Determines the output starting point. The full range of output can be seen as values in the range between 0 and 100 %. The offset
displaces this range. 50 % offset centres the range of output at the set point. 0 and 100 % offset result in having the full range of
output above or below the set point. See the table below for illustration of how the output behaves according to the input and with
different offsets.
DESIGNER'S HANDBOOK 4189341275A EN Page 188 of 196
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