Danfoss AK-CC 750A User Manual page 94

Stepper Motor Valves
When selecting a Danfoss stepper motor valve, all settings are fac-
tory set. Here, it is only necessary to select the type of valve.
If a valve from other manufacturers is used the following settings
has to be made. Get data from the valve manufacturer:
Max Operating Steps.
The number of steps that correspond to a valve position of 100%.
This value is limited to a range of 0 - 10,000 steps.
Hysteresis
The number of steps needed to correct for mechanical hysteresis
when a reduction gear is part of the valve design.
This adjustment is only applied, if an additional opening of the
valve is requested.
If this is the case the valve opens an additional amount equal to
this value, before driving the valve in the closing direction by this
same value.
This value is limited to 0 – 127 steps.
Step Rate
The desired valve drive rate in steps per second.
This value is limited to 20 – 500 steps / sec.
Holding Current
The percent of the programmed Max Phase Current that should
be applied to each phase of the stepper output when the valve is
stationary. If required, this current ensures that the valve main-
tains its last programmed position. This value is limited to a range
of 0 – 70% given in 10% steps.
Overdrive at Valve Init
During valve initialization, the amount to overdrive the valve,
beyond the 0% position, to ensure that the valve has fully closed.
This value is limited to a range of 0 - 31%.
Phase Current
The current applied to each phase of the stepper motor during
actual valve movement. This value is limited to 7 bits and a range
of 0 – 325 mA given in 10ma steps. Verify the range against the
stepper valve controller in the actual design.
Please be aware, that this value hat to be set in a RMS value. Some
valve manufacturers are using peak current!
Soft Landing after Valve Init
At power on the valve is performing a valve Initialization i.e.
closing the valve with "Max Operating Steps" plus "Overdrive At
Valve Init "steps to generate a zero point calibration of the system
. Hereafter a "Soft landing after Valve Init" is made to minimize the
closing force on the valve seat with a few opening steps according
to setting of "Hysteresis" or min 20 steps
Failsafe Position
During failsafe mode of operation (e.g., resulting from a loss of
communications to this module), specifies the default valve posi-
tion. This value is limited to a range of 0 – 100%.
94 RS8HP102 © Danfoss 2018-09
AKS 32R info
The signal from one pressure transmitter can
be received from up to 5 controllers
Graphic display MMIGRS2
A display gives access to most of the controller functions .
For access, connect the display to the controller and activate the address
on MMIGRS2. (A separate power supply does not need to be connected)
Power is supplied directly from the controller via the cable.
Setting:
1.Press both the "x" and "enter" buttons and hold in for 5 seconds. The
BIOS menu is then displayed.
2. Select the "MCX selection" line and press "enter"
3. Select the "Man selection" line and press "enter"
4. The address will be displayed. Check that it is 001, press "enter".
Data will then be collected from the controller.
Light-emitting diodes on the controller
Internal communication
between the modules:
Quick flash = error
Constantly On = error
Status of output 1-8
■ Power
■ Comm
■ DO1 ■ Status
■ DO2 ■ Service Tool
■ DO3 ■ LON
■ DO4 ■ I/O extension
■ DO5 ■ Alarm
■ DO6
■ DO7 ■ Display
■ DO8 ■ Service Pin
Slow flash = OK
Quick flash = answer from gateway
remains on for 10 mins after network
registration
Constantly ON = error
Constantly OFF = error
External communication
Communication to AK-CM 102
Flash = active alarm/not acknowledged
Constant ON = Active alarm/acknowledged
Network installation
AK-CC 750A