Danfoss AK-PC 420 User Manual page 19

3. P regulation with fixed setting
As point 1, but with P regulation the actual regulation temperature will
always deviate in relation to the actual reference. The reason is that the
actual cut-in capacity is solely dependent on how far the measured
regulation temperature is from the actual reference.
The capacity of the three-way valve is controlled via proportional band
"n04 Valve Xp" and the fans are controlled via proportional band "n60
4. P regulation with floating reference
As point 2, but with P regulation the actual regulation temperature will
always deviate in relation to the actual reference. The reason is that the
actual cut-in capacity is solely dependent on how far the measured
regulation temperature is from the actual reference.
The capacity of the three-way valve is controlled via proportional band
"n04 Valve Xp" and the fans are controlled via proportional band "n60
AK-PC 420
Heat recovery = on
Heat recovery = on
Manual RS8EL402 © Danfoss 03-2010
Fan Xp". This means that the three-way valve will be fully open when the
temperature is "n04 S7/Pc Xp" over the actual reference, and the fans will
provide full capacity when the temperature is "n04 S7/Pc Xp" + "n60 S8 Xp"
above the actual reference.
The cutin and cutout of fans are shown in the drawing.
If the entire fan capacity is controlled by speed regulation, the capacity will
be indicated on the broken line.
Fan Xp". This means that the three-way valve will be fully open when the
temperature is "n04 S7/Pc Xp" over the actual reference, and the fans will
provide full capacity when the temperature is "n04 S7/Pc Xp" + "n60 S8 Xp"
above the actual reference.
The cutin and cutout of fans are shown in the drawing.
If the fan capacity is controlled by speed regulation, the capacity will be
indicated on the broken line.
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