Wind readings quite high after battery change?

[Mark19]

Hello,
I have a WH1080 Weather station, and I decided to change the batteries on the transmitter unit yesterday, as they had been there over a year and the console was starting to loose contact with it more regularly.
However since doing this I have noticed that my wind speed readings are very high, it is windy outside but I don't think its as windy as it sensor says.
The other data such as temperature, humidity, pressure, rain and wind direction seem to be fine. I tried plugging the wind cable into another transmitter unit that I have spare to compare temperatures, but still get the same result.

Any ideas what could be wrong?

Thanks,
Mark

[AllyCat]

Hi Mark,

It depends how much higher are the readings (it is quite windy today) and where you are seeing the speed (Console screen or within Cumulus?).

Possibilities are that you're now displaying Gust instead of Average, km/hr in place of mph, or perhaps the receiver has locked onto somebody else's sensor.

The anemometer rotor generates two pulses per revolution, perhaps it was previously only one, or now the reed switch has some "contact bounce". But these are basically "mechanical" issues which are unlikely to be caused by changing the battery (voltage).

Cheers, Alan.

[steve]

I had a quick look at your site and it seemed to be displaying speeds comparable to other sites in Cornwall.

[NO0C]

The anemometer rotor generates two pulses per revolution, perhaps it was previously only one, or now the reed switch has some "contact bounce". But these are basically "mechanical" issues which are unlikely to be caused by changing the battery (voltage).

Are you sure of that My anemometer sensor has a single magnet and single reed switch and only pulses one time/revolution.

[Mark19]

I think it might be a to do the anemometer location. It is situated on a post about 4m above the ground. next to a flat roof extension of my house which is one story tall. The main house (2 story) is about 6 meters East of the anemometer, which probably blocks the wind a bit from that direction, this normally isn't much of a problem as normally winds from that direction arn't this strong, and every other direction is quite exposed.

I should also add that the wind gusts only seem to go extreme once in a while, and other times look fine.

Could the obstacle of the house be making the wind faster when it gets around the corner of the house from a certain direction?

This would make sense if true, as looking at my graphs the wind changed direction roughly when I changed the batteries.

Thanks

[AllyCat]

Are you sure of that My anemometer sensor has a single magnet and single reed switch and only pulses one time/revolution.

Hi Tim,

Yes, I'm absolutely sure that it is (or should be) two pulses, the magnet is offset and has two poles.
Various threads have discussed it, for example see here.

Cheers, Alan.

[NO0C]

Thanks Alan.

Upon further review ..... an ohmmeter on a spare sensor I have does indeed reveal that there are 2 pulses/revolution.

Interesting phenomenon.

Thanks for blowing the cobwebs out of my gray matter.

[Werk_AG]

...as looking at my graphs the wind changed direction roughly when I changed the batteries.

Hummm... can this be a clue?!!!

Some sensors need to be "re-calibrated" when changing batteries. In my case I need to stop wind speed meter, and manually point wind direction detector to North, before insert new batteries. Read you station manual to see it you need to do some similar procedure, before insert new batteries.

[Mark19]

I have looked through the manual, the only details it gives on about inserting batteries is in the initial start up bit. It says to put them in the transmitter first then the Console, I have been doing it the opposite way round, maybe this could cause a data read problem.

I will try it this way tomorrow.

[AllyCat]

Hi,

The reason for restarting the Console after changing the transmitter batteries is for it to re-synchronise to the transmitter pulses. However, this may not be necessary at all, if the transmitter batteries are changed quickly (ideally, immediately after the LED flashes). Doing it in the reverse order can potentially lead to permanent "--"s (loss of contact) on the Console display, but AFAIK no loss of calibration (at least of wind speed and direction).

No, there is no need to "recalibrate" the wind direction with the FO system, it's done with fixed magnetic reed switches within the sensor body.

Cheers, Alan.

[Charlie]

...as looking at my graphs the wind changed direction roughly when I changed the batteries.

Hummm... can this be a clue?!!!

Some sensors need to be "re-calibrated" when changing batteries. In my case I need to stop wind speed meter, and manually point wind direction detector to North, before insert new batteries. Read you station manual to see it you need to do some similar procedure, before insert new batteries.

Not sure what station you have, but for the WH1080 the original poster uses, this advice is complete nonsense.

[Werk_AG]

I just tried to help ... to my station (Venturis clone), the indicated procedure is described in the user manual. My apologies, if to others this is complete nonsense.

"Hold the wind vane pointing due north and do not allow it to turn.
Insert 2 pieces of AA batteries."

[Charlie]

Sorry - I didn't mean to choose such harsh words. But rest assured, none of the major weather stations require you to hold sensors in a specific position when you insert the batteries. It sounds like you have a really unusual beast. Can you point to a link for your station? I can't seem to find anything on it with a search engine...

[Werk_AG]

No problem Charlie.

Auriol Weather Station / Auriol h13726a
HAMA EWS 1500 Weather Station
Celestron Deluxe Weather Station
Meteoscan Weather Station

All of those above are clone of Ventus w155 Weather Station. Link to manual: http://www.ventusdesign.com/uploads/tx_ ... ish_01.pdf

Mine is a Auriol h13726a. It's a cheap and possibly unusual weather station. It even don't have a connection to PC. I'm using an Arduino to catch the RF signal from sensors (from the station I only use Wind Speed / Direction and the Pluviometer). Outside Temp / Hum and Barometric data, are from sensors (DHT22 and Bosh BMP085) connected to the Arduino.

I have starting with all of this because I like to play with Arduino, but now I'm really enthusiastic with this matter, and starting to learn more.

[Mark19]

Well my problem seems to have corrected itself, it must have been the turbulence cause by the house or something.

However now my spare transmitter which I keep in my homebuilt Stevenson screen to compare temperatures with my main transmitter seems to have stopped working, it just shows a flickering red led from batteries are put in which doesn't go out, and doesn't transmit data to the console for it.
The spare transmitter and console are 433.9 MHz, so a different frequency from the main station so they don't clash.

Anyone know how to fix, or will I need a replacement transmitter?