Danfoss EKC 315A, User Manual, Page: 5 / 16

EKC 315A Manual RS8CS302 © Danfoss 07-2005 5
Control parameters
P: Amplification factor Kp
If the Kp value is reduced the regulation becomes slower.
n04 Kp factor
I: Integration time Tn
If the Tn value is increased the regulation becomes slowe
n05 Tn sec.
D: Differentiation time Td
The D-setting can be cancelled by setting the value to min. (0).)
n06 Td sec.
Max. value for the superheat reference n09 Max SH
Min. value for the superheat reference
Warning! Due to the risk of liquid flow the setting should not be lower than approx.
2-4 K.
n10 Min SH
MOP
If no MOP function is required, select pos. Off.
n11 MOP (Bar)
(A value of 60 bar corresponds to Off)
AKV valve's time period in seconds
Should only be set to a lower value if it is a decentralised plant and the suction pres-
sure fluctuates a lot and in line with the opening of the AKV valve.
n13 AKV per. time
Stability factor for regulation of superheat
With a higher value the control function will allow a greater fluctuation of the super-
heat before the reference is changed. The value should only be changed by specially
trained staff.
n18 Stability
Damping of amplification near reference value
This setting damps the normal amplification Kp, but only just around the reference
value. A setting of 0.5 will reduce the KP value by half.
The value should only be changed by specially trained staff.
n19 Kp Min
Amplification factor for the superheat (AKV only and only in 1:1 plant)
This setting determines the valve’s opening degree as a function of the change in
evaporating pressure. An increase of the evaporating pressure will result in a reduced
opening degree. When there is a drop-out on the low-pressure thermostat during
start-up the value must be raised a bit. If there is pendling during start-up the value
must be reduced a little.
The value should only be changed by specially trained staff.
n20 Kp T0
Definition of superheat regulation (Ref. appendix 6)
1: Lowest permissible superheat (MSS). Adaptive regulation.
2: Load-defined superheat. The reference is established based on the line formed by
the three points: n09, n10 and n22.
n21 SH mode
Value of min. superheat reference for loads under 10%
(The value must be smaller than ”n10”).
n22 SH Close
Standby temperature when valve closed (TQ only)
The TQ actuator is kept warm when the valve reaches its closing point. As the closing
point cannot be defined completely accurately due to tolerances and pressure varia-
tions, the setting can be changed, as required (how ”tightly”/securely the valve is to
close). See also appendices 1 and 5.
n26 TQ Kmin
Standby temerature when valve open (TQ only)
The TQ actuator’s temperature is kept low when the valve reaches its fully open posi-
tion. Here you set how many degrees the temperature is to be above the expected
open temperature in completely open position. The greater the value, the surer it
is that the valve will be open, but it will also react more slowly when it has to close
again.
n27 TQ Kmax
Max. opening degree (AKV only)
The valve’s opening degree can be limited. The value is set in %.
n32 AKV/A OD Max