2
* Starting/stopping defrost.
The defrost cycle is automatically started and stopped. Programming by the internal parameters. During
defrost the led 'defrost' will light-up.
If there is a defrost cycle, the defrost can be stopped by hand, pushing the
UP
key and then the
SET
key, while the
UP
key is held.
If there is no defrost cycle, the defrost can be started by hand, pushing the
UP
key and then the
SET
key, while the
UP
key is held.
* Adjustment sensor.
The sensor can be adjusted by using the ‘Sensor Offset’ (parameter 04). Indicates the
ALFA(NET) 15
e.g. 2
C too much, the Sensor Offset has to be decreased by 2
C.
* Error messages.
In the display of the
ALFA(NET) 15
the following error messages can appear:
Er
- Sensor broken. Solution:
- Check if the sensor is connected correctly.
- Check the sensor (1000
at 25
C).
- Replace the sensor.
EE
- Settings are lost. Solution:
- Reprogram the settings.
* Technical details.
Model
: ALFA 15 Cool/Defrost Thermostat
ALFANET 15 Cool/Defrost Thermostat with Network
Range
: -50/+50
C, readout per 1
C
Supply
: 230 Vac / 1,2VA 50/60Hz (or else see product sticker)
Relay
: SPDT 250V/16A(C-NO), 8A(C-NC) (cos phi=1)
Control
: by pushbuttons on the front.
Communication
: RS 485 Network (2xtwisted pair shielded) only at ALFANET model.
Front
: Polycarbonate IP65
Sensor
: SM 811/2m (1000
at 25
C)
Sizes
: 90 x 53 x 58mm (hwd)
Panel hole
: 46 x 53mm (hw)
- Provided with memory protection during power failure.
- Connection with screw terminals on the backside.
- Equipped with self test function and sensor failure detection.
- Special versions are available upon request.
* Setting internal parameters.
Next to the adjustment of the setpoint, some internal settings are possible like differential, sensor-
offset, setpoint range and the defrost function.
By pushing the
DOWN
key for more than 10 seconds, you enter the 'internal programming menu'. In
the left display the upper and lower segments are blinking. With 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
or
DOWN
keys allows you to change the value of this parameter.
If no key is pushed for 20 seconds, the
ALFA(NET) 15
changes to it's normal operation mode.
