Danfoss FC 300 Design Manual page 37

FC 300 Design Guide
The following is an example of Process PID Control used in a ventilation system:
In a ventilation system, the temperature is to
be settable from 23 - 95°F (- 5 - 35°C) with a
potentiometer of 0-10 Volt. The set temperature
must be kept constant, for which purpose the
Process Control is to be used.
The control is of the inverse type, which means that
when the temperature increases, the ventilation
speed is increased as well, so as to generate more air.
When the temperature drops, the speed is reduced.
The transmitter used is a temperature sensor with
a working range of 14 -104°F (-10-40°C), 4-20
mA. Min. / Max. speed 300 / 1500 RPM.
NOTE
The example shows a two-wire transmitter.
Start/Stop via switch connected to terminal 18.
1.
2. Temperature reference via potentiometer (23 - 95°F (-5 - 35°C), 0-10 VDC) connected to terminal 53.
Temperature feedback via transmitter (14 -104°F (-10-40°C), 4-20 mA) connected to
3.
terminal 54. Switch S202 set to ON (current input).
Introduction to FC 300
MG.33.B6.22 - VLT is a registered Danfoss trademark
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