1
User Manual
ALFA 21 and
ALFANET 21
Cool/Heat
Thermostat
0-100
O
C
VDH doc: 070706
Version: v1.0
Date: 04-07-2007
Software: 053273_ALFA 11/21/31 0-100 File: Do070706.wpd
Range: 0/+100
C per 1
C
* Function.
The
ALFA(NET) 21
is a digital thermostat for panel mounting. The function from
the thermostat can be programmed for cooling or heating.
The
ALFA
NET
21
has a RS 485 network connection so it can be read out and
adjusted on the Alfanet.
* Installation.
On the topside of the
ALFA(NET) 21
is shown how the sensor, power supply and
relay have to be connected.
After connecting the
ALFA(NET) 21
to the power supply, a self-test function is
started. As this test is finished, the measured temperature appears in the display.
When the relay is activated, the led 'on' will light-up in the display.
* Control.
The
ALFA(NET) 21
Thermostat can be controlled by three push buttons on the
front.
These keys are:
SET
- view / change the setpoint.
UP
- increase the setpoint.
DOWN
- decrease the setpoint.
