D) Aligning Rain Sensor - elv WS 250 Edition Bedienungsanleitung

d) Aligning rain sensor

The measuring system of the rain gauge has already been set ex works to a high
level of exactitude.
Any alignment is therefore normally not necessary.
The alignment process takes fairly long (at least 10 minutes) and has to be carried out very
exactly and conscientiously as, otherwise, the exactitude is much lower than that which already
exists.
Proceed as follows for alignment:
• First of all, set any rain quantity value which may have accumulated back to zero.
For this, press the „RAIN" key in normal display mode for about two seconds. After releasing
the key, the display of the total rain quantity must indicate „0".
• Make sure that the rain gauge is clean and the count rocker dry.
• Pour 100 ml of clear water very slowly (distributed over 10 minutes) into the cone collector of
the rain sensor.
CAUTION!
If the water is poured too quickly, it results in an inaccurate measuring result.
Pour the water into the cone so slowly that at no point of time water stands in
the cone.
• The total quantity displayed should be 6.5 l/m
• If any other value is displayed, the so-called rocker value is to be recalculated as follows:
New rocker valuet =
• This new value has to be entered in the configuration menu (see section 9. a), „enter alignment
value of rain sensor") .
It is always entered in ml/rocker beat, the unit on the right is the subsequent
display unit of rain quantity!
The setting ex works is 295 ml/rocker beat (the "current rocker value" for the formula above).
2
.
6.5 x current rocker value
Actual value (display after filling with water)
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