Danfoss EKE 1A User Manual page 59

Superheat controller, Type EKE 1A, 1B, 1C, 1D
Table 51: Parameters Non-Danfoss valves: for Danfoss vales these parameters are preconfigured, if the user decides to use a
valve from a different manufacturer, then these parameters must be provided by the user.
Parameter Function
I027 Valve Motor Type
I028 Valve drive current
I029 Valve step positioning
I030 Valve Total Steps
I031 Valve speed
I032 Valve start speed
I061 Valve emergency speed
I062 Valve acceleration current
I063 Valve Acceleration Time
I077 Holding Current
I064 Valve step Mode
I065 Valve duty cycle
I070 Start Backlash
I071 Start backslash
I072 Overdrive
I076 Valve Excitation Time After Stop
© Danfoss | Climate Solutions | 2022.06
Description
Define a type of motor used in the stepper valve (Unipolar/Bipolar).
Setting the Peak current requirement of the motor in mA.
 NOTE:
Please be aware that this value must be set in a Peak value. Some valve manufacturers are
using RMS current (1mA RMS = 1.41mA Peak).
Defines which position step the valve motor should stop, while changing the opening degree
of the valve.
Choose between:
• Full-step
• Half-step
• Auto - controller will automatically choose based on the valve type right arrow Half step if
Unipolar valve |Full step whereas Bipolar valves
The number of steps that correspond to a valve position of 100%. The total no of steps will
vary according to the selected Valve motor type. For example: ETS 6 has total number of 480
half steps on driving with half phase excitation whereas only 240 full steps on driving with
Full phase excitation.
The desired valve drive rate in steps per second.
 NOTE:
Higher valve speed will produce a lower torque. If the valve is used in system having high
differential pressure, it is better to operate the valve with lower step rate
Valve initial speed as % of the valve speed (I031). The parameter Is used to avoid high acceler-
ation rate of the stepper motor.
 NOTE:
Make sure to select a start speed which is recommended for the used valve.
During power failure conditions, the valve can be driven at higher speed when required to
close faster. To run this feature, it is required to connect EKE with backup battery.
To control the torque in the start and stop sequence, the unit is % of the normal valve driving
current I028 (I031). Note that the torque of the motor is directly proportional to the supplied
current
 NOTE:
Make sure not to exceed the rated current of the valve motor, because this might damage it.
Defines the time of the acceleration/ deacceleration in the start/stop of the motor.
For some valves, this represents the percent of the programmed Max Phase Current that
should be applied to each phase of the stepper motor to maintain the valve at its last pro-
grammed position. Not all valve designs require a holding current, make sure to check this
with your valve manufacturer
Stepper motor can be driven with various step excitation method, which depends valve re-
quirements as well as operating conditions of an application.
The user can choose
• Full stepping 1/1
• Half stepping 1/2
• Micro-stepping (1/4, 1/8, 1/16)
 NOTE:
For half and micro stepping, the risk of step loss is higher because the torque provided is low-
er
Danfoss recommends using 1/8 stepping mode as this provides a good balance between tor-
que, speed, and smooth operation.
Defines the valve motion and stop time in a window of 60 seconds.
The parameter defines the operation of the start backlash function. The valve will normally
open from this point onwards.
The number of steps needed to correct for mechanical hysteresis when a reduction gear is
part of the valve design.
The extra steps taken to secure the closure of the valve.it is defined as a percentage of the full
opening.
The time that the drive current is applied after the motor has stopped before going to hold-
ing current. This will make sure that the valve has achieved the final position before going to
holding current.
BC398828796060en-000101 | 59