VDH ALFA 19 User manual

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User manual
ALFA 19 and
ALFANET 19
Hygrostat.
VDH doc: 071729 Version: v1.1 Date: 06-12-2007
Software: 061196_ALFA 19/29/39 File: Do071729.wpd Range: 0/100%RH per 1%RH
* Function.
The ALFA(NET) 19 is a digital hygrostat for rail mounting. The function from the hygrostat can be
programmed for humidify or dehumidify.
The ALFANET 19 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) 19 is shown how the sensor, power supply and relay have to be
connected.
After connecting the ALFA(NET) 19 to the power supply, a self-test function is started. As this test is
finished the measured humidity appears in the display.
When the relay is activated, the led 'on' will light-up in the display.
*Control.
The ALFA(NET) 19 hygrostat can be controlled by three push buttons on the front.
These keys are:
SET - view / change the set point.
UP - increase the set point.
DOWN - decrease the set point.
*Viewing setpoint.
By pushing the SET key the setpoint appears in the display. The led 'set' starts blinking. A few seconds
after releasing the SET key the set point disappears and the measured humidity is shown in the display.
*Changing setpoint.
Push the SET key and the set point appears in the display. Release the at SET key. Now push the SET
key again and together with the UP or DOWN keys the set point can be changed. A few seconds after
releasing the keys the measured humidity shows again in the display.

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*Adjustment sensor.
The sensor can be adjusted by using the Sensor Offset (parameter 04). Indicates the ALFA(NET) 19
e.g. 2% too much, the Sensor Offset has to de decreased with 2%.
*Error messages.
In the display of the ALFA(NET) 19 the following error messages can appear:
EE- Settings are lost. Solution:
- Reprogram the settings.
* Technical details.
Model :ALFA(NET) 19 Humidify/dehumidify Hygrostat
Range :0/+100%RH, readout per 1%RH
Supply :230 Vac 50/60Hz
Relay :SPDT 250V/16A(C-NO), 8A(C-NC) (cos phi=1)
Control :by push buttons on the front.
Communication :RS485-Network (2x twisted pair shielded, min. 0,75mm2)
Front :Polycarbonate
Sensor :0-1Vdc (0-100%RH) from RH95-2, LC95-2 or RH970
Be aware! Humidity sensors should be external supplied with 12Vdc
Sizes :90 x 53 x 58mm (hwd)
Panel hole :46 x 53mm (hw)
- Provided with memory protection during power failure.
- Connection with screw terminals on the back side.
- Special version on request available.
* Function diagram.

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*Setting internal parameters.
Next to the adjustment of the setpoint, some internal settings are possible like differential, sensor-
offset, set point range and the function humidify or dehumidify.
By pushing the DOWN key more than 10 seconds, you 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 keys together with the SET key allows you to change the value of this parameter.
If after 20 seconds no key is pushed, the ALFA(NET) 19 changes to it's normal operation mode.
*Parameters ALFA(NET) 19.
PARA-
METER
DESCRIPTION PARAMETER RANGE STANDARD
VALUE
01
02
03
04
Switching differential
Minimum set point
Maximum set point
Offset humidiy sensor
1..15 %RH
0..100 %RH
0..100 %RH
-15..+15 %RH
3
0
100
0
10 Startup delay after power failure 0..99 Minutes 0
15
16
17
18
19
20
Function hygrostat
Switch on delay relay 1)
Switch off delay relay 1)
Parameter 16/17 in sec. or min.
Minimum on-time relay
Minimum off-time relay
0 = Dehumidify
1 = Humidify
0..99
0..99
0 = Seconds
1 = Minutes
0..99 Minutes
0..99 Minutes
0
0
0
0
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
-
-
-
-
-
1) If delay is active, the led will flash
*Address.
VDH Products BV Tel: [phone]
Produktieweg 1 Fax: [phone]
9301 ZS Roden Email: [e-mail]
The Netherlands Internet: www.vdhproducts.nl

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*Dimensions. * Connections.