wviewweather.com

sly · Joined: 15 Oct 2006 Posts: 4

Hi all,

I'm using a wireless VP2 with a "Anemometer Transmitter Kit" (placed ~280m from the console).... wview is running fine and also writing the archive records (taken every 5min) into a mysql-database Wink

Unfortunately I'm stumbling quite often over some "-1" values for WindDir and HiWindDir (mostly during the night and mostly with the value "0" for WindSpeed and HiWindSpeed.... in some rare cases the HiWindSpeed shows "410.295").... according to the "wview User Manual" this "-1" value is written if undefined in the Archive Record... but what's the reason for such a undefined value?! is the distance of 280m too far? that's what I thought first ... and I did a couple of placements experiments:

- placing the console only about 40m next to the anemometer kit (signal strength: ~45-53) and the ISS about 240m far away
- placing the console ~280m from the anemometer kit (with direct intervisibility --> signal strength: from 20 up to 36)
- placing the console ~280m from the anemometer kit and using a repeater in the middle of the distance. with intervisibility to the console [~130m] and to the anemometer kit [~150m] --> signal strength: ~30-37

each combination was tested for at least 18h... but without any success: there were always some "-1" values (WindDir and HiWindDir ) in the archive... while the ISS values are fine... even while the console was placed 240m away!!!!

due to these placement experiments I could reduce my presumptions to the following points:

- the anemometer kit has a defect
which would be a strange kind of defect since during daytime and especially during some windy periods at daytime the rate of "no"-undefined values within the is 100%

- the anemometer kit is sending NO data in absolute calm conditions
the "0"-values for WindSpeed and HiWindSpeed while "-1" appears for WindDir and HiWindDir may tempt to such a presumptions ... but fact in some rare cases a single "-1" value appears just in between 2 correct values with windspeeds of over 5km/h in a period of several hours with more than 5km/h.... hard to believe that the wind just stopped bowing for 5 minutes... futher I would have to measure the wind values with another anemometer to enforce this presumptions ... but what about the rare cases where the HiWindSpeed shows "410.295"? this is not reproducible with another anemometer Wink

- an external disruption is affecting the transmission
which is also hard to believe because: A) the console recieved all values form the ISS... even while the ISS was placed 250m from the console during 5h of strong rain... and B) the "-1" values are appearing at 95% during the night... but the "-1"-spreading looks quite accidentally and is different from night to night

did anyone out there make similar experiences? or does anyone have a solution for my problem?

well.... I'll keep looking but any help is highly appreciated!
thanks in advance, sly!

sly · Joined: 15 Oct 2006 Posts: 4

me again.... looks like my problem is solved: according to the support of davisnet.com the datalogger does store "---" for WindDir if there was absolutly no wind during the archive interval and wview does translate this to "-1".

cheers, sly