VDH ALFANET 55 RTDF, User Manual

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User manual
ALFA 55 RTDF and
ALFANET 55 RTDF
Cool/Defrost
thermostat with
fan-control and
realtime defrost.
VDH doc. 030087 Version: v2.1 Date: 10-03-2008
SW: 992649_ALFA(NET) 55/65/75 RTDF File: Do030087.wpd Range: -50,0/+50,0  C pro 1  C
* Description.
The ALFA(NET) 55 RTDF is a cool/defrost thermostat for rail-mounting, with various defrost-, and fan-
control settings. The thermostat has 6 Real-Time DeFrost time settings a day available.
The
ALFA NET 55 RTDF has a RS 485 network connection so it can be read out and adjusted on the
Alfanet.
* Installation.
On the connection diagram of the ALFA(NET) 55 RTDF is shown how the sensor, power supply and
relays has to be connected.
After connecting the
ALFA(NET) 55 RTDF to the power supply, a self test function is started. As this
test is finished, the measured temperature of the control-sensor appears in the display.
* Control.
The ALFA(NET) 55 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.
MODE - relay status key.
* 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 MODE key, the display shows the status of the relays. Each display segment shows the
status of the relay output, showing =off, =on and on the last segment=natural defrost active.
The code means relay 1(compr.) and 2(fan) are on and relay 3(defr.) is off.