Jump to content
Snow?
Local
Radar
Cold?
IGNORED

Help With Annometer


Recommended Posts

Posted
  • Location: Runcorn, Cheshire
  • Weather Preferences: Snowy winters, hot, sunny springs and summers.
  • Location: Runcorn, Cheshire

I bought a new weather station which came with an annometer (wind speed thing) my garden is rather sheltered but it still picks up wind, it's about 3 meters off the ground but it's picking up the wrong wind direction and hardly any speed. Can anyone help me with this?

Link to comment
Share on other sites

Posted
  • Location: Derbyshire Peak District. 290 mts a.s.l.
  • Weather Preferences: Anything extreme
  • Location: Derbyshire Peak District. 290 mts a.s.l.

The wind direction fault could be one of two things. Firstly you need to set up the direction indicator on the anemometer head with the reading on the indoor unit. To do this you need a compass with which to find North, when you've found North point the direction vane towards it and then make sure the indoor reading is showing the same (it's easier to do this with two people, one to hold the wind vane towards north and the other to look at the display indoors )

If you've already done this and the reading is still not as it should be, it could be that with your site being sheltered there are wind eddies around obstructions which cause the vane to move around the compass no matter what the general wind direction is. The only real answer, if this is the case, is to get the anemometer higher or away from obstructions.

If your anemometer is failing to show wind speed when you think there should be a reading it's either due to the anemometer head being over sheltered, in which case the only answer is to get it higher up, or the anemometer head has a high start up speed.

Some less expensive units won't show any speed at all below about 5 knots which is well above the speed where the leaves on the trees would be moving. It should tell you the anemometer start up speed in the technical instructions with your unit, sometimes it's listed as 'sensitivity '.

Good luck.

Edited by Terminal Moraine
Link to comment
Share on other sites

Posted
  • Location: Runcorn, Cheshire
  • Weather Preferences: Snowy winters, hot, sunny springs and summers.
  • Location: Runcorn, Cheshire

The wind direction fault could be one of two things. Firstly you need to set up the direction indicator on the anemometer head with the reading on the indoor unit. To do this you need a compass with which to find North, when you've found North point the direction vane towards it and then make sure the indoor reading is showing the same (it's easier to do this with two people, one to hold the wind vane towards north and the other to look at the display indoors )

If you've already done this and the reading is still not as it should be, it could be that with your site being sheltered there are wind eddies around obstructions which cause the vane to move around the compass no matter what the general wind direction is. The only real answer, if this is the case, is to get the anemometer higher or away from obstructions.

If your anemometer is failing to show wind speed when you think there should be a reading it's either due to the anemometer head being over sheltered, in which case the only answer is to get it higher up, or the anemometer head has a high start up speed.

Some less expensive units won't show any speed at all below about 5 knots which is well above the speed where the leaves on the trees would be moving. It should tell you the anemometer start up speed in the technical instructions with your unit, sometimes it's listed as 'sensitivity '.

Good luck.

Thanks for that great post TM! I shall go grab a compass and line it up now. It was a £70 weather station but seems to be picking up speeds of 1mph so it must be okay :doh:

rrp £100.00

Edited by Hancock
Link to comment
Share on other sites

Posted
  • Location: Runcorn, Cheshire
  • Weather Preferences: Snowy winters, hot, sunny springs and summers.
  • Location: Runcorn, Cheshire

The wind direction fault could be one of two things. Firstly you need to set up the direction indicator on the anemometer head with the reading on the indoor unit. To do this you need a compass with which to find North, when you've found North point the direction vane towards it and then make sure the indoor reading is showing the same (it's easier to do this with two people, one to hold the wind vane towards north and the other to look at the display indoors )

If you've already done this and the reading is still not as it should be, it could be that with your site being sheltered there are wind eddies around obstructions which cause the vane to move around the compass no matter what the general wind direction is. The only real answer, if this is the case, is to get the anemometer higher or away from obstructions.

If your anemometer is failing to show wind speed when you think there should be a reading it's either due to the anemometer head being over sheltered, in which case the only answer is to get it higher up, or the anemometer head has a high start up speed.

Some less expensive units won't show any speed at all below about 5 knots which is well above the speed where the leaves on the trees would be moving. It should tell you the anemometer start up speed in the technical instructions with your unit, sometimes it's listed as 'sensitivity '.

Good luck.

I think I did it... there was a line under the weather vein telling me to point it north, but it was already pointing north. The wind direction is still being a pain, one minute it's reading west then it's reading south, then north. :doh:

Link to comment
Share on other sites

Posted
  • Location: Derbyshire Peak District. 290 mts a.s.l.
  • Weather Preferences: Anything extreme
  • Location: Derbyshire Peak District. 290 mts a.s.l.

If your anemometer is picking up speeds of 1 mph then it's certainly not the start up speed, any lack of wind speed shown by the anemometer must be down to the sheltered nature of your site.

Unfortunately it's not always easy to get round this problem, not many of us live with wide open expanses of country on all sides and sometimes it's just a case of making the best of what you've got.

Ideally you could do with the anemometer mounted on a mast on the house roof to get it as far above any obstructions as possible but that's not always as easy as it sounds, particularly if it's your parents' house ( I noticed you are 16 so I'm assuming it's not your own place ) and they're not keen on a mast sticking up above the roof line.

If the anemometer has to be where it is you'll still find it interesting just to see what wind speeds you get in your own back garden. You'll also notice that if it gets really windy you'll be recording gusts which are way above the low average speed of a sheltered site.

The main thing is that you've got the interest in the first place.

Link to comment
Share on other sites

Posted
  • Location: Runcorn, Cheshire
  • Weather Preferences: Snowy winters, hot, sunny springs and summers.
  • Location: Runcorn, Cheshire

If your anemometer is picking up speeds of 1 mph then it's certainly not the start up speed, any lack of wind speed shown by the anemometer must be down to the sheltered nature of your site.

Unfortunately it's not always easy to get round this problem, not many of us live with wide open expanses of country on all sides and sometimes it's just a case of making the best of what you've got.

Ideally you could do with the anemometer mounted on a mast on the house roof to get it as far above any obstructions as possible but that's not always as easy as it sounds, particularly if it's your parents' house ( I noticed you are 16 so I'm assuming it's not your own place ) and they're not keen on a mast sticking up above the roof line.

If the anemometer has to be where it is you'll still find it interesting just to see what wind speeds you get in your own back garden. You'll also notice that if it gets really windy you'll be recording gusts which are way above the low average speed of a sheltered site.

The main thing is that you've got the interest in the first place.

Oh yes, I have a lot of interest :doh:

One question though. If i put it on the top of the house, it would be out of sight and not pointing at the main weather station inside. The range on it is 40 meters, which is obviously much higher than a house. Would the weather station still pick up the signal if it isnt facing it?

Hey! I had a 8mph gust in here yesterday! :lol: :lol: !

Link to comment
Share on other sites

Posted
  • Location: Derbyshire Peak District. 290 mts a.s.l.
  • Weather Preferences: Anything extreme
  • Location: Derbyshire Peak District. 290 mts a.s.l.

Oh yes, I have a lot of interest :doh:

One question though. If i put it on the top of the house, it would be out of sight and not pointing at the main weather station inside. The range on it is 40 meters, which is obviously much higher than a house. Would the weather station still pick up the signal if it isnt facing it?

Hey! I had a 8mph gust in here yesterday! :lol: :lol: !

Not sure on that, it depends on the model you've got. One way to find out, without going to the trouble of putting it on the roof and finding it doesn't work, would be to move it somewhere in the garden, pointing away from the main station and see if it still works; if it does you should be o.k

Link to comment
Share on other sites

Posted
  • Location: Runcorn, Cheshire
  • Weather Preferences: Snowy winters, hot, sunny springs and summers.
  • Location: Runcorn, Cheshire

It does work pointing away from the station yes. But the wind direction is all bloody wrong! Payed alot of money for this weather station only to find that it cant get the wind direction right! I can do a better job than that with a leaf and a compass! :)

Parents can't even get on the roof, they wont let me put it up there. :)

Link to comment
Share on other sites

Posted
  • Location: Derbyshire Peak District. 290 mts a.s.l.
  • Weather Preferences: Anything extreme
  • Location: Derbyshire Peak District. 290 mts a.s.l.

It does work pointing away from the station yes. But the wind direction is all bloody wrong! Payed alot of money for this weather station only to find that it cant get the wind direction right! I can do a better job than that with a leaf and a compass! :)

Parents can't even get on the roof, they wont let me put it up there. :)

In what way is the wind direction wrong? Is it moving all around the compass without settling for long on any one direction or is it consistently showing one direction even though it's the wrong one?

It's difficult to pinpoint the problem without actually seeing the site but if you've got obstructions such as buildings, trees or even a steep bank which are higher than the anemometer head it can cause all sorts of problems with the wind direction due to swirling and eddying around the obstructions.

If you've previously oriented the anemometer vane to north at one location and then moved it to another location in the garden, to see if it works pointing away from the main station, you'll have to re-set it to north again at the new location; if you don't, the wind direcion indicated will almost certainly be wrong.

Link to comment
Share on other sites

Posted
  • Location: Runcorn, Cheshire
  • Weather Preferences: Snowy winters, hot, sunny springs and summers.
  • Location: Runcorn, Cheshire

Its switching every 2 mins. I shall take a picture of where it is and a few pics of my weather station. It's really annoying! It's an enclosed yard. It's surrounded by everything

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=230378493806&ssPageName=STRK:MEWNX:IT

Thats the station I have.

Link to comment
Share on other sites

Posted
  • Location: Derbyshire Peak District. 290 mts a.s.l.
  • Weather Preferences: Anything extreme
  • Location: Derbyshire Peak District. 290 mts a.s.l.

Its switching every 2 mins. I shall take a picture of where it is and a few pics of my weather station. It's really annoying! It's an enclosed yard. It's surrounded by everything

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=230378493806&ssPageName=STRK:MEWNX:IT

Thats the station I have.

How often does the wind direction information coming from the anemometer head update on the indoor display?

Is it a continuous readout of direction or does it only update every so many seconds?

I ask this because of your comment above that, 'it's switching every two minutes' which implies that it's not a continuous read out but updates every so often.

If this is the case, and you've got the anemometer in a sheltered yard, it's very likely that, due to wind eddies around the local obstructions, the wind direction will be different every time it updates.

If it's a continuous readout on the display you'll find the indicator moving all around the dial without ever really settling on one direction, or the equivalent if it's a digital display showing letters for the direction.

There's no way around this problem other than to get the anemometer head above the local obstructions, if you can't do that I'm afraid you'll have to make do with very erratic wind speed and direction information.

Link to comment
Share on other sites

Posted
  • Location: Runcorn, Cheshire
  • Weather Preferences: Snowy winters, hot, sunny springs and summers.
  • Location: Runcorn, Cheshire

How often does the wind direction information coming from the anemometer head update on the indoor display?

Is it a continuous readout of direction or does it only update every so many seconds?

I ask this because of your comment above that, 'it's switching every two minutes' which implies that it's not a continuous read out but updates every so often.

If this is the case, and you've got the anemometer in a sheltered yard, it's very likely that, due to wind eddies around the local obstructions, the wind direction will be different every time it updates.

If it's a continuous readout on the display you'll find the indicator moving all around the dial without ever really settling on one direction, or the equivalent if it's a digital display showing letters for the direction.

There's no way around this problem other than to get the anemometer head above the local obstructions, if you can't do that I'm afraid you'll have to make do with very erratic wind speed and direction information.

Got an arrangement to get it on the roof! It sends wind readings every 60 seconds.

Link to comment
Share on other sites

Posted
  • Location: Derbyshire Peak District. 290 mts a.s.l.
  • Weather Preferences: Anything extreme
  • Location: Derbyshire Peak District. 290 mts a.s.l.

Got an arrangement to get it on the roof! It sends wind readings every 60 seconds.

In that case I'm 99% sure that the problem is due to being in a sheltered yard with obstructions all around it.

Good luck with getting it on the roof, the higher the better.

Link to comment
Share on other sites

Posted
  • Location: Runcorn, Cheshire
  • Weather Preferences: Snowy winters, hot, sunny springs and summers.
  • Location: Runcorn, Cheshire

In that case I'm 99% sure that the problem is due to being in a sheltered yard with obstructions all around it.

Good luck with getting it on the roof, the higher the better.

Cheers for the good advice there TM! We have to ask the guy around the shop in the corner who fits CB ariels, we dont have a big enough ladder. :)

Link to comment
Share on other sites

Posted
  • Location: Nr Appleby in Westmorland
  • Location: Nr Appleby in Westmorland

Don't forget, your gust readings might be MUCH lower than the actual gusts you get.

I have a Vantage Pro 2, and that updates itself every 2.5 seconds. That means that the highest gust reading is the highest average 2.5 seconds' worth of wind, not the highest gust within that 2.5 second period. Therefore, if your device updates every minute, the likelihood is your highest gust reading is actually going to be the highest minute's worth average wind speed, and NOT the highest gust within any one minute.

This might seem frustrating, but it still allows comparisons and shows the relative wind strength compared to any other period. The main differences between cheaper and more expensive weather stations is, as far as I can make out, the frequency they update their wind readings.

So, if it's a really windy day out there, and your device only shows a maximum gust of 20mph, don't be surprised.

Link to comment
Share on other sites

Posted
  • Location: Derbyshire Peak District. 290 mts a.s.l.
  • Weather Preferences: Anything extreme
  • Location: Derbyshire Peak District. 290 mts a.s.l.

Don't forget, your gust readings might be MUCH lower than the actual gusts you get.

I have a Vantage Pro 2, and that updates itself every 2.5 seconds. That means that the highest gust reading is the highest average 2.5 seconds' worth of wind, not the highest gust within that 2.5 second period. Therefore, if your device updates every minute, the likelihood is your highest gust reading is actually going to be the highest minute's worth average wind speed, and NOT the highest gust within any one minute.

This might seem frustrating, but it still allows comparisons and shows the relative wind strength compared to any other period. The main differences between cheaper and more expensive weather stations is, as far as I can make out, the frequency they update their wind readings.

So, if it's a really windy day out there, and your device only shows a maximum gust of 20mph, don't be surprised.

That's a very good point, OON. Agree entirely about the difference between the lower and upper end of the market, I was looking for a system which would update every second but there's nothing available under about £2000.

Link to comment
Share on other sites

Posted
  • Location: Derbyshire Peak District. 290 mts a.s.l.
  • Weather Preferences: Anything extreme
  • Location: Derbyshire Peak District. 290 mts a.s.l.

I've seen analogue meters which have a maximum needle which might therefore record the precise highest gust. Perhaps they're the £2000 ones though?

Not sure. The stuff I was looking at was all digital, from places like Casella and Munro for anemometers, and Delta T and Skye, to name but two, for complete automatic weather stations.

Delta T do some excellent stuff but for the accuracy and response times I wanted it was at least £4000 for a complete set up.

Munro and Casella do Met' office standard anemometers and vanes with 1 second response times but you're looking at £1500 upwards just to record the wind speed and direction before you start on anything else.

I might buy a lottery ticket today, just in case.

Link to comment
Share on other sites

Posted
  • Location: Runcorn, Cheshire
  • Weather Preferences: Snowy winters, hot, sunny springs and summers.
  • Location: Runcorn, Cheshire

To be honest i'm sick of this station... It decides when it wants to pick up the wind speed, and decides when it takes a rain measurement. It's either broken or a complete waste of £70.

No matter what I do... Nothing happens. I feel like chucking it through the window.

Link to comment
Share on other sites

Posted
  • Location: Nr Appleby in Westmorland
  • Location: Nr Appleby in Westmorland

It doesn't really matter when it makes a rainfall measurement does it, as long as it keeps a record of the total amount. Perhaps it only updates the rainfall and temperature at a different interval to the wind measurements?

TM - this is the sort of thing I was meaning - http://www.novalynx.com/200-500.html and http://www.weather-instruments-online.com/Maestro-Brass-silver-dial.htm

Put wind speed dial into Google and it comes up with these sort.

Edited by Osbourne One-Nil
Link to comment
Share on other sites

Posted
  • Location: Runcorn, Cheshire
  • Weather Preferences: Snowy winters, hot, sunny springs and summers.
  • Location: Runcorn, Cheshire

It doesn't really matter when it makes a rainfall measurement does it, as long as it keeps a record of the total amount. Perhaps it only updates the rainfall and temperature at a different interval to the wind measurements?

TM - this is the sort of thing I was meaning - http://www.novalynx.com/200-500.html and http://www.weather-i...silver-dial.htm

Put wind speed dial into Google and it comes up with these sort.

It's supposed to update every 60 seconds... It isnt recording anything at all at any time.

Could it be the batteries? because my mum just went to town to get some super powered batteries. :D

It's currently reading the right wind direction believe it or not. Shame it isnt doing anything else.

Wow... THE TEMPERATURE READING IS ALSO WRONG!! :rolleyes::rolleyes::wallbash::wallbash:

Link to comment
Share on other sites

Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

hi H

is this picture in the link below what you have?

http://www.amazon.co...K/dp/B0006FOAR8

or this?

http://cgi.ebay.co.u...=item35a3a0d76e

Edited by johnholmes
Link to comment
Share on other sites

Posted
  • Location: Derbyshire Peak District. 290 mts a.s.l.
  • Weather Preferences: Anything extreme
  • Location: Derbyshire Peak District. 290 mts a.s.l.

It doesn't really matter when it makes a rainfall measurement does it, as long as it keeps a record of the total amount. Perhaps it only updates the rainfall and temperature at a different interval to the wind measurements?

TM - this is the sort of thing I was meaning - http://www.novalynx.com/200-500.html and http://www.weather-instruments-online.com/Maestro-Brass-silver-dial.htm

Put wind speed dial into Google and it comes up with these sort.

I've not seen these makes before, I must be blinkered by digital. The Novalynx one certainly seems good at the price, 3% accuracy across that sort of range is not bad at all. It doesn't actually state what the response time of the unit is, I'll Google it and try and find out more. As you mentioned above in another post, if the response time is two seconds then the needle on the dial will only show the highest 2 second average although in reality this will be pretty close to the actual gust speed and to the highest gust speed recorded by any unit, other than something of the calibre of a Dines anemograph for which you'd need a small mortgage.

Link to comment
Share on other sites

Posted
  • Location: Taunton, Somerset
  • Weather Preferences: Snow, thunder, strong winds
  • Location: Taunton, Somerset

I've got this station, pretty good for casual observation and seems to be pretty accurate aswell. Will set you back around £200 but I'm pleased with what I've got for my money. I live in the middle of the countryside, but it is still important to have the anemometer as high as you can. The rain gauge needs to be in an open location, preferably around only 1 metre above the ground otherwise strong winds will effect the rain measurement.

http://www.weather-station-products.co.uk/item--LaCrosse-weather-station-WS3600--WS3650.html

Link to comment
Share on other sites

Posted
  • Location: Nr Appleby in Westmorland
  • Location: Nr Appleby in Westmorland

It doesn't actually state what the response time of the unit is, I'll Google it and try and find out more.

Seeing as it's connected by a cable, like an old-fashioned bike (or your penny farthing) speedo might have used, I imagine it must be real-time.
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • UK Storm and Severe Convective Forecast

    UK Severe Convective & Storm Forecast - Issued 2024-03-29 07:13:16 Valid: 29/03/2024 0600 - 30/03/2024 0600 THUNDERSTORM WATCH - FRI 29 MARCH 2024 Click here for the full forecast

    Nick F
    Nick F
    Latest weather updates from Netweather

    Difficult travel conditions as the Easter break begins

    Low Nelson is throwing wind and rain at the UK before it impacts mainland Spain at Easter. Wild condtions in the English Channel, and more rain and lightning here on Thursday. Read the full update here

    Netweather forecasts
    Netweather forecasts
    Latest weather updates from Netweather

    UK Storm and Severe Convective Forecast

    UK Severe Convective & Storm Forecast - Issued 2024-03-28 09:16:06 Valid: 28/03/2024 0800 - 29/03/2024 0600 SEVERE THUNDERSTORM WATCH - THURS 28 MARCH 2024 Click here for the full forecast

    Nick F
    Nick F
    Latest weather updates from Netweather
×
×
  • Create New...