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Reference manual RS8ED102 © Danfoss 03-2006
EKC 316A
Types of regulation
Single Loop (address o56 Reg.type = 1)
The EKC 316A has the
traditional
PI controlling function with the
Kp factor for Proportional Gain and Tn for Integration Time in se-
conds. This also is known as the Single loop control with only one
PI block as shown in the diagram below.
Evaporator Temp. S1
PI Control
Refrigerant Temp.
S2
Superheat Ref.
SHref
Superheat
(S2 – S1)
+
-
+
-
ETS Valve
Evaporator
Kp factor and Tn settings
Instability cause by too much Proportional Gain can be corrected
by reducing to value of the Kp factor. This should be done redu-
cing with small steps at a time and observing the results before
making further reductions.
If the superheat response is slow to changes, it can be increased
by reducing the value of the Integration Time Tn.
When tuning the superheat stability, it is good practise to have a
fixed superheat reference by making SH max the same as SH min.
