VDH Products ALFANET 75, User Manual

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* Manual starting/stopping of defrost.
The defrost cycle is automatic started and stopped. These defrost settings thru internal parameters.
Stop defrost:
If there is a defrost cycle , the defrost can be manually stopped by pushing the UP
and the DOWN key simultaneously.
Start defrost: If there is no defrost cycle , the defrost can be manually started by pushing the UP
and the DOWN key simultaneously.
* Setting internal parameters.
Next to the adjustment of the setpoint, some internal settings are possible like differentials, sensor-
adjustments, setpoint-range, compressor-, fan-, defrost- and alarm-settings.
By pushing the
DOWN key for more than 10 seconds, you enter the 'internal programming menu'.
In the left display the upper and the lower segments are blinking. Over the UP and DOWN keys the
required parameter can be selected (see table for the parameters).
If the required parameter is selected, the value can be read-out by pushing the
SET key. Pushing
the UP and DOWN keys allows you to change the value of this parameter.
If after 20 seconds no key is pushed, the ALFANET 75
changes to it’s normal operation mode.
* Sensor adjustment.
The temperature-sensor can be adjusted by using the Offset control sensor (parameter 05).
The defrost-sensor can be adjusted by using the Offset defrost sensor (parameter 07).
For read out of the defrost sensor on the display use parameter 06.
Indicates a sensor e.g. 2

C too much, the according Sensor-offset parameter has to be decreased
with 2

C.
* Error messages.
In the display of the ALFANET 75 the following error messages can appear:
LO - Minimum alarm Solution E1/E2:
HI - Maximum alarm - Check if sensor is connected correctly.
E1 - Control sensor failure - Check sensor (1000

/25

C).
E2 - Defrost sensor failure - Replace sensor.
EEE - Settings are lost. Solution EEE:
- Reprogram the settings.
-L- - In case of sensor short-circuit the display alternates between error-code E..
and -L- , as indication for a short-circuit sensor.
-H- - In case of open-circuit sensor the display alternates between error-code E..
and -H- , as indication for a open circuit sensor.
Reset Alarm. When a error-messages appears it can be reset by pushing the SET key. The
function of this key depends on parameter P37.
* Alarm.
As a failure or alarm occurs an error message is shown in the display. The ALFANET 75
remembers it’s error message, although it is already solved. The error message is resettable with
the
SET key. As if after pressing the SET key (=reset alarm) the alarm still is not solved than the
ALFANET 75 displays the temperature and the error message alternated, is the alarm solved, then
the error message disappears and the temperature is displayed normally.