Danfoss EKE 1A User Manual page 20

Superheat controller and stepper valve driver, Type EKE 1A, 1B, 1C, 1D
4 Applications
EKE series devices are used where precise control of superheat in air conditioning system is needed. It helps
achieving high energy e ciency and reliable operation
EKE serves 2 main applications:
• Controller Mode
◦ Standalone Superheat control
◦ Temperature control
• Driver Mode
The need for cooling can either be de ned by the incoming media (S3) or the outgoing media (S4) temperature
4.1 Controller Mode
4.1.1 Superheat control mode
EKE can serve as a PI controller for stepper motor valve that controls the superheat of the evaporator based on a
pressure Pe and temperature (S2) sensors. In superheat mode the controller will control the superheat to be stable
and close to the superheat reference. If superheat is too low the ow in the expansion is decreased and superheat
will be higher
Figure 18: Superheat control application
EKE 1X
EEV
4.1.2 Temperature control mode
Temperature control Can be accomplished via a signal from temperature sensor S3 placed in the air ow before the
evaporator or S4 placed in the air ow after the evaporator.
EKE has 2 methods of controlling temperature:
• ON/OFF thermostat
• Modulating thermostat (MTR)
The temperature control can be done using an ON/OFF thermostat that opens/closes the stepper valve as per S3/S4
temperature values or modulating thermostat that regulates the stepper valve more smoothly based on S3/S4
temperature setpoints. The need for cooling can either be de ned by the incoming media (S3) or the outgoing
media (S4) temperature
© Danfoss | Climate Solutions | 2024.08
Pe
S2
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