VDH ALFA(NET) 52 User Manual

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User manual
ALFA(NET) 52 0/+100C
Double Thermostat.

VDH doc. 072384 Version: v1.0 Date: 18-10-2007

Software: ALFA 52 0-100C File: Do072384.WPD Range: 0/+100C

* Installation.

On the connection diagram of the ALFA(NET) 52 is shown how the sensors, power supply and
relays has to be connected. After connecting the ALFA(NET) 52 to the power supply, a self test
function is started. As this test is finished, the measured temperature of thermostat-1 appears in the
display. Thermostat-1 works with sensor-1 and relay-1. Thermostat-2 works with sensor-2 and
relay-2. Relay-3 can function as alarm relay or functions as second stage of thermostat-2.

* Control.

The ALFA(NET) 52 thermostat can be controlled by four pushbuttons on the front These keys are:

SET - view / change set point and reset the alarm

 (UP) - increase the set point.
 (DOWN) - decrease the set point.

MODE - relays status key.

* Viewing the temperature of sensor-2.

By pressing the UP key, the measured temperature of sensor-2 is shown in the display. After
releasing the key, the measured temperature of sensor-1 is shown again in the display.

* Viewing set points.

Viewing set point of thermostat-1:

By pushing the SET key and then simultaneously pushing the UP key, the set point of
thermostat-1 appears in the display.

Viewing set point of thermostat-2:

By pushing the SET key and then simultaneously pushing the DOWN key, the set point of

thermostat-2 appears in the display.
A few seconds after releasing the keys the set point disappears and the measured temperature of
thermostat-1 is shown again in the display.

* Changing set points.

Push the SET key together with the UP or DOWN key in order to select the desired set point (see
above). Release the SET key. Now push the SET key again together with the UP or DOWN keys to
change the set point. A few seconds after releasing the keys, the measured temperature of sensor­1 is shown again in the display.

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

* Setting internal parameters.

Next to the adjustment of the set point, internal settings can be made like differential, sensor offset,
set point range and the functions of the thermostat.
Push the DOWN key more than 10 seconds, to enter the 'Internal Programming Menu'. In the left
display the upper and lower segment are blinking. Over the 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 key to change the value of this parameter.
If after 20 seconds no key is pushed, the ALFA(NET) 52 changes to the normal operation mode.

* Adjustment sensors.

Sensor-1 can be adjusted by using the Sensor Offset parameter 05 and Sensor-2 can be adjusted
by using the Sensor Offset parameter 06. Indicates a Sensor e.g. 2C to much, the according
Sensor Offset has to be decreased with 2C.

* Error messages.

In the display of the ALFA(NET) 52 the following error messages can appear:

Lo1 - Minimum alarm thermostat-1. Solution E1,E2:

Hi1 - Maximum alarm thermostat-1. - Check if the sensor is connected correctly.

Lo2 - Minimum alarm thermostat-2. - Check sensor (1000 at 25C).

Hi2 - Maximum alarm thermostat-2. - Replace sensor.

E1 - Sensor-1 failure.

E2 - Sensor-2 failure. Solution EEE:

EEE - Settings are lost. - Reprogram the settings.

-L- - In case of sensor short-circuit the display alternates between error-code E..
and -L-, as indication for a short-circuit sensor.

-H- - In case of open-circuit sensor the display alternates between error-code E..
and -H-, as indication for a open circuit sensor.

Reset Alarm. When an error-messages appears it can be reset by pushing the SET key. The

function of this key depends on parameter P42.

* Technical data ALFA(NET) 52.

Type : ALFA(NET) 52 Double thermostat (Rail-mounting)
Range : 0/+100C per 0,1C
Supply : 230Vac 50/60Hz (-5/+10%)
Readout : 3-digit 7-segment display
Relays : Ry1= SPST(NO) 250V/8A(cos =1) or 250V/5A (cos =0.4)

Ry2= SPST(NO) 250V/8A (cos =1) or 250V/5A (cos =0.4)
Ry3= SPDT(NO/NC) 250V/8A (cos =1) or 250V/5A (cos =0.4)

Relays have one common (C).
Control : By push buttons on front.
Front : Polycarbonate
Sensors : 2x SM 811/2m (PTC 1000/25C).
Communication : RS 485 Network (2xtwisted pair shielded) only at ALFANET model.
Dimensions : 90 x 71 x 58mm (HWD)
Panel cutout : 46 x 71mm (HW) at front mounting
Accuracy : ± 0,5% of the range.

- Provided with memory protection during power failure.

- Connections with screw terminals on the back side.

- Equipped with sensor failure detection.

- Special versions on request available.

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* Parameters ALFA(NET) 52

Para­Meter

Description Parameter Range Standard

value

01

02

03

Function relay 1

Function relay 2

Function relay 3

1=Cool
2=Heat
3=Alarm
1=Cool
2=Heat
3=Alarm
1=Cool
2=Heat
3=Alarm

1

1

3

0506Offset temperature sensor-1

Offset temperature sensor-2

-15..+15C

-15..+15C

0
0

10
11
12
13
14
15

Switching differential relay 1
Set point offset relay 1
Switching differential relay 2
Set point offset relay 2
Switching differentia relay 3
Set point offset relay 3

0.1..15

-15..+15

0.1..15

-15..+15

0.1..15

-15..+15

0.5
0

0.5
0

0.5
0

20
21
22

23
24

Switch on delay cooling
Switch off delay cooling
Parameter 20/21 in Sec. or Min.

Minimum on-time cooling
Minimum off-time cooling

0..99

0..99
0=Seconds
1=Minutes

0..99 Minutes

0..99 Minutes

0
0
0

0
0

2526Minimum set point

Maximum set point

0..+100C

0..+100C

0

+100

30

31
32
33
34

35

36
37
38
39

40
41
42

Alarm type thermostat-1 (to set point)

Minimum alarm set point-1
Maximum alarm set point-1
Time delay minimum alarm-1
Time delay maximum alarm-1

Alarm type thermostat-2 (to set point)

Minimum alarm set point-2
Maximum alarm set point-2
Time delay minimum alarm-2
Time delay maximum alarm-2

Relay function alarm relay
Reset alarm relay after recovering alarm
Reset alarm relay after manual reset

0= None
1= Absolute
2= Relative

0..+100C

0..+100C

0..99 min.

0..99 min.
0= None

1= Absolute
2= Relative

0..+100C

0..+100C

0..99 min.

0..99 min.
0= Watch

1= Control
0= No
1= Yes
0= No
1= Yes

1

0

+100

0
0

1

0

+100

0
0

0
0
0

0

45
46
47

Start up delay after power failure
Forced relay-1 on at sensor-1 failure
Forced relay-2(,3) on at sensor-2
failure

0..99 Minutes
0= No, 1=Yes
0= None
2= Relay-2 on
3= Relay-3 on

0
0

90
95
96
97
98
99

Network number
Software version
Production year
Production week
Serial number (x1000)
Serial number (units)

1..255

0..255

00..99

1..52

0..255

0..999

1
0
0
1
0
0

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* Dimensions. * Connections.

* Adress.

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