Alfanet 75 RTDF User Manual

User manual
ALFANET 75 RTDF
Cool/Defr. Thermostat
with fan-control and
realtime defrost.
VDH doc.020994
Software: ALFA(NET) 75 RTDF

* Description.

The ALFANET 75 RTDF is a cool/defrost thermostat with various defrost- and fan-control settings.
And it is controllable on the PC thru the ALFANET PC-INTERFACE.

* Installation.

On the top side of the ALFANET 75 RTDF is shown how the sensor, power supply and relays has
to be connected.
After connecting the ALFANET 75 RTDF to the power supply, a self test function is started. As this
test is finished the measured temperature of the temperature-sensor (control) appears in the
display.

* Control.

The ALFANET 75 RTDF thermostat can be controlled by four push buttons on the front. These
keys are:
SET - view / change the setpoint.
UP - increase value.
DOWN - decrease value.
 C - hidden push button above SET key and behind  C symbol.

* View setpoint.

By pushing the SET key the setpoint appears in the display. The decimal point of the last display
starts blinking to indicate this. After a few seconds after releasing the SET key the setpoint
disappears and the measured temperature is shown again.

* Changing setpoint.

Push the SET key and the setpoint appears in the display. Release the SET key. Now push the
SET key again together with the UP or DOWN keys to change the setpoint. After a few seconds
after releasing the SET key the setpoint disappears and the measured temperature is shown again.

* Status of the Relays.

By pushing the hidden  C key the display shows the status of the relays. Each display segment
shows the status of the relay output, showing
defrost active.
The code means relay 1(compr.) and 2(fan) are on and relay 3(defr.) is off.
Version: v1.2
File: DO020994.WP8
=off, =on and
1
Date: 15-02-2005
Range: -50,0/+50,0  C
on the last segment=natural