Problem with windspeed graph

[DaveNZ]

I thought you'd changed it so as the Davis provided the average value ?
In which case nothing has changed ?

I like to have cumulus calculate the average so I get a smooth line on my graphs. The Davis station rounds the average unfortunately, so the values are set at 6.4, 8.0, 9.7, 11.3 etc and so the average line jumps up and down. I switch the option off before I shut cumulus at night because of the issue raised in another thread (where windspeed will spike up next time cumulus is started).

Anyway I wouldn't think this should affect how cumulus is reading the data from the Davis DLL...

[steve]

Calm conditions here between 5 and 6 this morning - cumulus has read the windspeed: "--- 0.0" correctly as 0.0 but has ignored the wind gusts which appear as "--- 0.0" and instead plot the last non-zero value recorded.
Hence the average line successfully hits zero but the gust line doesn't....

This is from the logger again, presumably? Could I have the diags file if so...

[steve]

I've just had a look at the code to see if I could see how this might be happening, and I spotted a change which I was sure I had done for the previous build is somehow 'undone'. It's possible that I did the change and somehow forgot to save the file, so it's not clear whether the build 885 binary actually has the change or not. Build 886 definitely does have the change, so see how that goes.

[DaveNZ]

Here's the diags file - looking through I saw some "wd=-32768" again.

cumulus.004

Cheers Steve, will install new build.

[DaveNZ]

Average and gust both hit 0 for a short time overnight - and the new build of Cumulus I installed reflects this in it's graphs
Although I do notice now that the wind direction for these calm periods is plotted at 0° (North) despite this option being unchecked in Cumulus...

[steve]

Although I do notice now that the wind direction for these calm periods is plotted at 0° (North) despite this option being unchecked in Cumulus...

As you have seen, the station is supplying -32767 for these periods. What value should I use, if not zero? Or would you rather it continued to use the last 'good' direction? I suppose I could do that...

[DaveNZ]

No it's ok....just before when it was calm (the older cumulus builds) there were just gaps in the graph instead of it going along 0º

[steve]

Ah, right. It's because it was ignoring all of the wind data, so those points didn't get plotted at all. It's a bit hard to do that now I'm actually processing the data. I think it would be better (given that I have to plot something) to continue to plot the previous good direction (unless the 'use zero for calm' option is selected). What happened to the direction when it was calm with live data? I guess I ought to try to do the same thing with logger data, even if the DLL/station behaves differently.

[DaveNZ]

What happened to the direction when it was calm with live data? .

Hmmm, I wish I knew! We usually only get the calm periods overnight, then a light breeze has usually developed within an hour or so after dawn.

[steve]

I thought a few posts ago you had said that the wind had dropped to zero before you closed down for the night?

[DaveNZ]

I thought a few posts ago you had said that the wind had dropped to zero before you closed down for the night?

Oh yes, sorry forgot about that! Just had a look through the Dec09 log and it did read as 0.0,0.0,0. So it did give 0º for calm direction while live.