TFA Dostmann 35.1023 Manual De Uso página 50

Before starting the calibration of the Rain Volume Sensor any possibly already
accumulated rain volume value has to be erased and reset to 0 in normal display
mode according to Item Rain of this manual (leaving the Programming Mode).
Following this procedure pour exactly one Liter of water during an arbitrary time
span very slowly into the funnel of the Rain Volume Sensor.
Caution!
Fast pouring will corrupt the measuring results! Pour the water so slow into
the funnel, that there is no slack water in the funnel at any time.
Recommendation!
In order for the water not to run too fast into the funnel, thus causing a faulty
calibration, place a small cup made of synthetic material into the funnel.
Prepare the cup by piercing a small hole into the bottom using a sharply pointed
tool. The water will now enter the funnel very slowly drop by drop.
Because of the 130mm diameter of the funnel, representing an area of 0.0133m
the amount of 1 Liter of water will yield a nominal rain volume of 75.34 Liter/m
After the entire amount of water has run through the funnel the actual value (displayed
value) will show on the display, in the ideal case 75.3 l/m
The ratio of Target Value to Actual Value will yield the Calibration Factor. Since this
calibration factor may have already been entered at an earlier date, it has to be
included in the calculation.
The new Calibration Factor can be computed in the following equation:
New Calibration Factor =
The old calibration factor can be viewed by simultaneously pressing the
(←) and (→) keys as well as the „Calibr." key in Calibration Mode. Select the display
field for the Rain Volume Sensor by use of the (←) key.
After the first data transmission from the Rain Volume Sensor the old calibration
factor will be shown on the display.
Correct the calibration factor to its new value by use of the "+" and "–" keys and
possibly the „Fast" key.
By pressing the „Store" key the set value is stored and the display will return to the
normal operating mode.
Change of Units
If the „Unit" key is pressed in Calibration Mode, the display section "Rain" will
allow the selection of the units l/m
will allow the selection of the units mm or hPa.
50
Target Value (e.g. 75.3 l/m
Actual Value (Display after passing 1 Liter of Water)
2 or mm and the display section "Air Pressure"
2
.
2
) x Old Calibration Factor
2 ,
2
.