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Is there a maximum anemometer speed?

Posted: Mon 07 Feb 2011 1:33 pm
by dionaea
Hi All,
Since last Thursday we have had a more or less continuous gale blowing in this area of North Norfolk - & as I write it is increasing in velocity once again.The fact that I am only about a mile from the sea may have something to do with it. I find it interesting that on each day at some point it has reached 50 mph but goes no higher for either average over 10 minutes or gust. Could it be that there is a maximum rotation speed for the anemometer? My station is a WH 1080.

Cheers,
Chris

PS Polythene greenhouse blew over on first night removing 6 " masonary screws & plugs from paving stones!

Re: Is there a maximum anemometer speed?

Posted: Mon 07 Feb 2011 1:50 pm
by steve
Possibly because of the ancient version of Cumulus you're using. I found an error some time ago in the unofficial Fine Offset spec that I was working from which meant that wind speeds above about 25 m/s could never be recorded. I can't remember when this was, exactly.

Was the console showing higher speeds than Cumulus?

Fine Offset stations are definitely capable of registering wind gusts in excess of 90 mph, as I found out recently.

Re: Is there a maximum anemometer speed?

Posted: Mon 07 Feb 2011 2:12 pm
by dionaea
Hi Steve,
I never tend to look at the console - I will now - you realise that this means that the wind velocity is bound to fall according to the ancient law of Sod! I am pretty sure that gusts have gone well over 51mph.
What should I upgrade to - 1.9.0 ?

Cheers,
Chris

Re: Is there a maximum anemometer speed?

Posted: Mon 07 Feb 2011 2:19 pm
by Orion
Hi
The latest beta 1.9.1 Build977 is very stable

Re: Is there a maximum anemometer speed?

Posted: Mon 07 Feb 2011 2:20 pm
by steve
I've dug out the old code, and 1.8.8 had the change in anyway; so the explanation must be that your station didn't record any higher wind speed. As I say, I know they are capable of much higher than 50 mph.

Re: Is there a maximum anemometer speed?

Posted: Mon 07 Feb 2011 4:25 pm
by robynfali
Not sure what version of cumulus it was, but it recorded a 63mph gust working perfectly, and the past 4 days, we have been under gale conditions quite constantly.....and there heading in again apparently!

So I dont think its any problem with that mate

Re: Is there a maximum anemometer speed?

Posted: Mon 07 Feb 2011 8:02 pm
by dionaea
Hi all,
Many thanks folks. I am looking at 1.9.1. Build 977 but am worried about losing over 2 years data. Have done a backup of the older version.
Like I said - the wind has fallen away so now I have no way of testing the anemometer until the next big storm.

Cheers,
Chris

Re: Is there a maximum anemometer speed?

Posted: Mon 07 Feb 2011 8:15 pm
by robynfali
you dont lose data, dont uninstall or anything, just stop cumulus, and install the new version, straight over the top, but untick "html pages" if you have modified any of your own

Re: Is there a maximum anemometer speed?

Posted: Tue 08 Feb 2011 1:33 am
by artworksmetal
You might want to set the Wind Gauge Range higher in the Display Configuration. Otherwise you might break the needle. :P

Re: Is there a maximum anemometer speed?

Posted: Tue 08 Feb 2011 12:25 pm
by timfy
Cumulus/fine offset proofed to one hundred mph here the other day (well 98 and a bit!).

No idea of theoretical maximum though.

Re: Is there a maximum anemometer speed?

Posted: Tue 08 Feb 2011 12:30 pm
by steve
The spec says 100 mph. But in reality...?

Re: Is there a maximum anemometer speed?

Posted: Tue 08 Feb 2011 7:49 pm
by dionaea
Hi All,
Thanks for all the replies - I have upgraded to 1.9.1 build 977 & must say I'm impressed so far - thanks for the advice Rob. Just got to do some fine tuning - colours, photo gallery etc. I have increased wind speed to 90mph in calibration. I wonder if that was the problem in the first place? Anyway Art, none of us wants a broken needle!! Also thanks Steve - again.
I suppose that there is no way of testing whether it will go over 50mph until we get the next big un ? A low flying jet perhaps!!

Cheers,
Chris

Re: Is there a maximum anemometer speed?

Posted: Tue 08 Feb 2011 8:01 pm
by dionaea
Hi Rob,
You said >but untick "html pages" if you have modified any of your own < Can you tell me where I find the box to untick please?

Cheers,
Chris

Re: Is there a maximum anemometer speed?

Posted: Tue 08 Feb 2011 8:07 pm
by mcrossley
The speed setting is just for the default display, if the wind speed exceeds that value then Cumulus re-scales the gauge.
This allows you to select the initial range for the wind gauge. When the wind speed gets above this value, the range will increase to 2x the value, then 3x, and so on. The minimum value you can supply is 5. Note that some values will cause the gauge scale to look rather odd; multiples of 5 are probably best.

Re: Is there a maximum anemometer speed?

Posted: Tue 08 Feb 2011 8:11 pm
by robynfali
dionaea wrote:Hi Rob,
You said >but untick "html pages" if you have modified any of your own < Can you tell me where I find the box to untick please?

Cheers,
Chris

If your installing the latest beta, it's AS your installing, just click carefully through each window on the install sequence, you will come across a white one that mentions html pages, just make sure thats unticked