VDH ALFA 71 PI User Manual

User manual
ALFA 71 PI and
ALFANET 71 PI
O
0/+100 C Thermostat.
VDH doc. 081208
Software: 020218_ALFA71PI 0/100°C

* Installation.

On the top side of the ALFA(NET) 71 PI is shown how the sensors, power supply, relays and 0..10Vdc
PI output has to be connected. After connecting the ALFA(NET) 71 PI to the power supply, a self test
function is started. As this test is finished the measured temperature appears in the display.
And the ALFANET -71 PI is by use of the ALFANET PC-INTERFACE controllable on the PC.

* Control.

The ALFA(NET) 71 PI thermostat can be controlled by four pushbuttons on the front. These keys are:
SET - view / change the setpoint.
UP - increase the setpoint.
DOWN - decrease the setpoint.
°C - hidden push button above the SET key and behind °C symbol.

* Viewing setpoint.

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

* 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. A few seconds after releasing
the keys the measured temperature shows again in the display.

* 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 0=off and 1=on. The code 110 means relay 1 and 2 are on and
relay 3 is off.

* Viewing the PI-output percentage.

Push the °C and UP keys simultaneously. Now the PI-output percentage is shown in the display.

* Viewing countdown timer for forced heating.

Push the °C and DOWN keys simultaneously. Now the time in hours is being displayed up to the next
forced heating action. If this time is less than 10 hours it will show the time and minutes to go,
seperated by a decimal dot (representation "h.mm"). At active forced heating the most right decimal
dot is lit.
Version: v1.3
File: Do081208.wpd
1
Date: 29-01-2015
Range: 0/+100°C