VDH ALFA 35 DP User manual

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User manual ALFA(NET) 35 DP
Cool/Defrost Thermostat.
VDH doc. 053813 Version: v1.3 Date: 12-05-2006
Software: ALFA(NET) 35 DP File: Do053813.WPD Range: -10/+40C per 0,1C
* Function.
TheALFA(NET) 35 DP is a digital thermostat forpanel mounting.Thethermostat controls the cooling
and defrost. Defrost will be done by temporarilyswitching off the cooling (natural defrost). The defrost
starts on intervals or on compressor runtime. The defrost stops on time.
TheALFANET 35 has a RS 485 network connectionsoit canbe readout and adjusted on the Alfanet.
*Installation.
On the topside op the ALFA(NET) 35 DP you can see how the sensor, power supply and relay have
to be connected.
After connecting the ALFA(NET) 35 DP 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.
TheALFA(NET) 35DPthermostatcanbecontrolledbythreepushbuttonsonthefront.Thesekeysare:
SET - view / change the setpoint.
UP - increase the setpoint.
DOWN - decrease the setpoint.
*Viewing setpoint.
Bypushing the SET keythe setpointappears inthedisplay.Afewsecondsafter releasingtheSET key
the setpoint disappears and the measured temperature is shown in the display.
*Changing setpoint.
Push the SET key and the setpoint appears in the display. Release the SET key. Now push the SET
keyagain and together with the UP or DOWN keys the setpoint can be changed. A few seconds after
releasing the keys the measured temperature is show in the display.
*Starting/stopping defrost.
Thedefrostcycleisautomaticallystartedandstopped.Programmingbytheinternalparameters.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.

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*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. Withthe 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) 35 DP changes to it's normal operation mode.
*Adjustment sensor.
Thesensor can be adjusted byusing the ‘Sensor Offset’ (parameter 04). Indicates the ALFA(NET) 35
DP 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) 35 DP 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(NET) 35 DP Cool/Defrost Thermostat
Range : -10/+40C, readout per 0,1C
Supply : 230 Vac (or 24Vdc or 12Vdc)
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 : 35 x 77 x 71,5mm (hwd)
Panel hole : 28 x 70mm (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.

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*Parameters ALFA(NET) 35 DP.
PARA-
METER DESCRIPTION PARAMETER RANGE STANDARD VALUE
01
02
03
04
Switching differential
Minimum setpoint
Maximum setpoint
Offset temperature sensor
1..15C
-10..+40C
-10..+40C
-15..+15C
3
-10
+40
0
05
06
Compressor start-up protection
0 = start-up delay in sec.
1 = start-up delay in min.
2 = delay between switch off and
switch on min.
3 = delay between switch on and
switch on min.
Compressor start-up time
belonging to parameter 05
0..3
0..99
0
10
07
08
09
10
11
12
13
14
15
Defrost cycle time
Defrost time
Defrost delay after power failure
(if parameter 14 is 1)
Startup delay after power failure
Relay on at sensor failure
Defrost cycle time based on
compressor on time
Temperature display locked
during defrost cycle
After power failure starting
with defrost cycle
Maximum time display locked after
defrost (if parameter 13 = 1)
1..99 hrs.
0..99 min.
0..99 min.
0..99 min
0 = No
1 = Yes
0 = No
1 = Yes
0 = No
1 = Yes
0 = No
1 = Yes
0..60 min.
12
15
0
0
0
0
0
0
5
90
95
96
97
98
99
Network number
Software version
Production year
Production week
Serial number (x1000)
Serial number (units)
1..250
0..255
00..99
1..52
0..255
0..999
1
-
-
-
-
-
* Function diagram.

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If applicable
*Dimensions.
*Connection diagram.
*Address.
VDH Products BV Tel: +31 (0)50 - 30 28 900
Produktieweg 1 Fax: +31 (0)50 - 30 28 980
9301 ZS Roden Email: [e-mail]
The Netherlands Internet: www.vdhproducts.nl