VDH ALFA 51 PI User manual

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User manual
ALFA 51 PI -10/+90C
Rail-Thermostat.
VDH doc. 070033 Version: v1.0 Date: 27-09-2007
Software: ALFA51-PI (–10+90) File: Do070033.WPD Range: -10/+90,0C
*Installation.
On the connection diagram of the ALFA 51 PI is shown how the sensors, analogue output, power supply
and relays are to be connected. After connecting the ALFA 51 PI to the power supply, a self test function
is started. As this test is finished, the measured temperature appears in the display.
*Control.
The ALFA 51 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.
MODE - relay status key.
*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.
*Viewing the individual sensors.
By pressing the UP and DOWN key together, the individual sensors can be shown in the display. After
releasing the keys, the measured temperature of sensor-1 can be shown by pushing the UP key or the
measured temperature of sensor-2 can be shown by pushing the DOWN key. A few seconds after
releasing the keys the (average) temperature shows again in the display.
*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.

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*Setting internal parameters.
Next to the adjustment of the setpoint, internal settings can be made like differential, sensor offset,
setpoint range and the functions of the thermostat.
Push the DOWN key for more than 10 seconds, to enter the 'Internal Programming Menu'. In the left
display the upper- and lower-segment are blinking. With the UP and DOWN keys the required parameter
can be selected (see the parameter table).
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 51 PI changes to the normal operation mode.
*Adjustment sensors.
Sensor-1 can be adjusted by using the Sensor Offset parameter 06 and Sensor-2 can be adjusted by
using the Sensor Offset parameter 07. Indicates a Sensor e.g. 2C to much, the according Sensor Offset
has to be decreased by 2C.
*Error messages.
In the display of the ALFA 51 PI the following error messages can appear:
LO - Minimum alarm. Solution E1,E2:
HI - Maximum alarm. - Check if the sensor is connected correctly.
E1 - Sensor-1 failure. - Check sensor (1000at 25C).
E2 - Sensor-2 failure. - Replace sensor.
EEE - Settings are lost. Solution EEE:
- 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 a error-messages appears it can be resetted by pushing theSET key. The
function of this key depends on parameter P37.
* Technical data.
Type : ALFA 51 PI rail thermostat
Range : -10/+90,0C, display per 0,1C
Supply : 12Vac 50/60Hz (-5/+10%)
Display : 3-digit 7-segment display
Relays : Ry1= SPST(NO) 250V/8A (cos =1) of 250V/5A (cos =0.4)
Ry2= SPST(NO) 250V/8A (cos =1) of 250V/5A (cos =0.4)
Ry3= SPDT(NO/NC) 250V/8A (cos =1) of 250V/5A (cos =0.4)
Relays have one common (C).
Control : By push buttons on front.
Front : Polycarbonate IP65
Sensors : SM 811/2m (PTC 1000/25C).
Analogue output : 0..10Vdc PI output (Rload = min. 10KOhm)
Dimensions : 90 x 71 x 58mm (HWD)
Panel cut out : 46 x 71mm (HW) for 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 are on request available.

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*Parameters ALFA 51 PI
Para-
Meter Description Parameter Range Standard value
01
02
03
04
Function Relay 1
Function Relay 2
Function Relay 3
Function PI-output
1 = Cool
2 = Heat
3 = Alarm
1 = Cool
2 = Heat
3 = Alarm
1 = Cool
2 = Heat
3 = Alarm
1 = Cool
2 = Heat
1
2
3
1
05
06
07
08
Offset temperature sensor
Offset PI (zone)
P-band setting
I-time setting
-15.0..+15.0C
-15.0..+15.0C
0.0..20.0C
0..99 minutes
0.0
0.0
5.0
0 (off)
10
11
12
13
14
15
16
17
18
19
Switch on relay 2 by
Switch on relay 3 by
Switch on delay relay 2
Switch on delay relay 3
Switching differential relay 1
Setpoint offset relay 1
Switching differential relay 2
Setpoint offset relay 2
Switching differential relay 3
Setpoint offset relay 3
0 = Temperature
1 = Time
0 = Temperature
1 = Time
0.. 99 Minutes
0..99 Minutes
0.1..15.0 C
-15..+15 C
0.1..15.0 C
-15..+15 C
0.1..15.0 C
-15..+15 C
0
0
15
15
0.5
0.0
0.5
0.0
0.5
0.0
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
25
26
27
Minimum set point
Maximum set point
Read-out per 1C
-10.0..+90.0C
-10.0..+90.0C
0 = No
1 = Yes
-10
+90
0
30
31
32
33
34
35
36
37
Alarm type (to setpoint)
Minimum alarm setpoint
Maximum alarm setpoint
Time delay minimum alarm
Time delay maximum alarm
Relay function alarm relay
Reset alarm relay after recovering alarm
Reset alarm relay after manual reset
0 = None
1 = Absolute
2 = Relative
-10.0..+90.0C
-10.0..+90.0C
0..99 Minutes
0..99 Minutes
0 = Watch
1 = Control
0 = No
1 = Yes
0 = No
1 = Yes
1
-10
+90
0
0
0
0
0
0
40
41 Start up delay after power failure Forced relay function at sensor failure 0..99 Minutes 0 = None
1 = Cool
2 = Heat
0
0
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
0
0
1
0
0

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*Dimensions. *Connections.
*Address.
VDH Products BV Tel: [phone]
Produktieweg 1 Fax: [phone]
9301 ZS Roden Email: [e-mail]
The Netherlands Internet: www.vdhproducts.nl