Page 1 of 1

Wind Direction Issue.

Posted: Fri 26 Aug 2011 6:56 pm
by Flying Eye
Hi all,

We don't have much wind right now, hopefully that will change soon, but not by too much, just enough to work with would be great! ;)

The problem is that what ever direction I see on the stations LCD screen, Cumulus does not always reflect the same direction. Sometimes it will agree with what the station is showing and sometimes it won't.

Is there anything I could have set wrong to make this be the case?

What can I do to make them agree?

As far as I have so far noticed all other settings do agree, but not wind direction. I'm stumped. I've tried all sorts, refresh rates, running as admin, not running as admin. It just seems a bit random, and if anything it's getting worse.

If I shut down Cumulus and run easy weather it does it all just fine. So that leads me to suspect I must have set something wrong? I'm not sure of the right place in Cumulus to start checking first. :?

Re: Wind Direction Issue.

Posted: Fri 26 Aug 2011 7:03 pm
by Flying Eye
DOH, use north when calm! That may have been it, we'll see! <dumb newb> :oops:

Re: Wind Direction Issue.

Posted: Fri 26 Aug 2011 7:08 pm
by steve
You're looking at the 'Bearing' in Cumulus rather than 'Avg Dir', yes?

Have you set an offset for wind direction in the calibration settings?

Are you allowing for the fact that it takes Cumulus up to 10 seconds to catch up with the console?

Have you set 'use zero bearing when calm'?

Can you give some examples of the console readings and Cumulus readings at the same time - allowing for Cumulus to catch up.

Re: Wind Direction Issue.

Posted: Fri 26 Aug 2011 7:17 pm
by Flying Eye
steve wrote:You're looking at the 'Bearing' in Cumulus rather than 'Avg Dir', yes?

Have you set an offset for wind direction in the calibration settings?

Are you allowing for the fact that it takes Cumulus up to 10 seconds to catch up with the console?

Have you set 'use zero bearing when calm'?

Can you give some examples of the console readings and Cumulus readings at the same time - allowing for Cumulus to catch up.
It was using zero when calm that was causing it as far as I know now.

So what use was that setting option intended for? A day or so back when it was not calm it looked tempting and sort of sensible, so I ticked it, but now I'm wondering why I'd want to to show anything other than what it really is. And that's probably my lack of experience making me think that way too! :lol:

Thanks for the tips Steve!

Re: Wind Direction Issue.

Posted: Fri 26 Aug 2011 7:27 pm
by steve
It's a standard (well, it is for the UK Met Office, at least) that a station reports zero for bearing when there is zero wind.

Re: Wind Direction Issue.

Posted: Fri 26 Aug 2011 7:34 pm
by Flying Eye
steve wrote:It's a standard (well, it is for the UK Met Office, at least) that a station reports zero for bearing when there is zero wind.
I see, if only they had picked 361 thus avoiding any chance of some one wondering if they meant north! :lol:

Thanks very much for clarifying.

There is so much to take in at first that it's easy to be a bit overwhelmed and thereby miss the blooming obvious. It was only after I asked, then hit submit that it dawned on me it might not be ignoring the station but just endlessly showing north. I just don't know why that mostly happens just after you hit the submit button! ;)

Re: Wind Direction Issue.

Posted: Fri 26 Aug 2011 7:43 pm
by steve
Flying Eye wrote:I see, if only they had picked 361 thus avoiding any chance of some one wondering if they meant north! :lol:
That's why the standard also defines North to be only 360 and not zero. But yes, someone who didn't know that might think zero was North. I don't think anyone will mind if you turn the setting off and display whatever direction the station is sending.

Re: Wind Direction Issue.

Posted: Fri 26 Aug 2011 7:56 pm
by Flying Eye
I was just pondering all that, and most of us know once we think about it that 1-360 is kosher, but I am also aware that an awful lot of people do use zero degrees to convey straight ahead, I am also wondering if it might have been this decision to use zero that got them doing that in the first place? I find the historic origins of these things is often fascinating.

One thing I have noted though is that now I have it unticked, the gauges show up fine and reflect the reality of the vane's direction, but the NOW page says "Wind Bearing 0° ---".

Not sure how to get it to be consistent for both, which feels like it should be the case. <shrug>

I could see me going back to zero for tradition's sake and then endlessly explaining it to others, or going with reality and having the two not being reconciled. I guess showing where it last came from is tempting, although I'm not sure of what use it could be. <shrug>

Looks a lot like a grey area by now! ;)

Re: Wind Direction Issue.

Posted: Fri 26 Aug 2011 8:03 pm
by steve
Flying Eye wrote:One thing I have noted though is that now I have it unticked, the gauges show up fine and reflect the reality of the vane's direction, but the NOW page says "Wind Bearing 0° ---".
The default index page supplied with Cumulus uses average bearing, which must be zero when the wind is calm, it couldn't be anything else. The thinking behind using the average bearing is that it's much more useful as a 'snapshot' than the 'instantaneous' bearing that the station supplies, particularly with Fine Offset wind vanes which tend to flap around semi-randomly.

If you want to display the instantaneous bearing, you can edit the indexT.htm file and replace <#avgbearing> with <#bearing> and <#wdir> with <#currentwdir>.