Wind gust and Wind speed merge when Cumulus off.

[Johnny25]

Hi

Only noticed this a couple of days ago and not sure if it's a Vantage Vue issue or a Cumulus issue.

When Cumulus is running and data is transferred from the logger everything is fine and the wind gust and wind speed are correct. However when I turn Cumulus off during the night and then turn it back on again in the morning, the uploaded data for wind gust and wind speed are the same. This is then giving 'wind gust' and 'highest wind speed average' as the same. Theoretically possible, but I would of thought highly unlikely.

http://warwick-weather.com/trends.htm - Cumulus was off just past 10pm and on just before 7am - data merges.

http://warwick-weather.com/yesterday.htm - Highest gust and Highest wind speed (10 min avg) are the same. Also the same on the monthly records for April & May.

Any explanation/solution to the issue would be welcome.

Thanks
Johnny

[steve]

See http://wiki.sandaysoft.com/a/FAQ#The_.E ... m_my_graph

[Johnny25]

Thanks Steve for the prompt response.

I changed the logging interval to 10mins and update to 10mins as well.

Johnny

[steve]

I changed the logging interval to 10mins

You've changed the station interval, and Cumulus to 10 minutes also, hopefully?

Note that there isn't an ideal solution anyway, other than running Cumulus all the time. Even at a 10 minute logger interval, Cumulus only has 1 value to calculate the average from, so it'll still come out the same. If you switch to using the average from the station, then when running live that's OK - the live data will be the same, as the station supplies a 10-minute average anyway, but that average isn't available from the logger; it's the 3-second average at the time the entry was logged.

[ejay]

Steve, maybe you can add an option to temporarily disable calculating a 10-minute average upon startup, and after it finishes reading from the data logger, automatically re-enable the 10-minute calculation? This would be really useful for Fine Offset owners who only run Cumulus during the day and switch off their PC overnight.

[steve]

Steve, maybe you can add an option to temporarily disable calculating a 10-minute average upon startup, and after it finishes reading from the data logger, automatically re-enable the 10-minute calculation? This would be really useful for Fine Offset owners who only run Cumulus during the day and switch off their PC overnight.

I don't understand how that would help? What would it use instead?

[ejay]

I'll explain it in more detail.

If I disable the Cumulus 10-minute calculation before shutting it down, and only re-enable it after Cumulus has finished reading the values from the console's data logger (e.g. from overnight), the logged gust and average wind speeds will be preserved.

If I forget to turn off the 10-minute option, and start up Cumulus the next day, I get the same problem as the OP (gust and average wind speeds become merged).

So, another option to automatically disable the Cumulus 10-minute average calculation whilst it is downloading and processing the data logger values would save me from having to do it manually (or forgetting and losing the discreet wind and gust readings).

[steve]

Ah, so presumably you're using the default setting of using the gust value for the average wind speed calculation? I keep thinking I should change the default anyway, after all of the adverse comments I get about it. Have you considered changing that option, or do you prefer the default?

The option you're proposing would be functionally identical to turning that option off during logger processing (assuming a logger interval of 10 mins or more) i.e Cumulus would use the station's average value instead. So, yes, I could offer that as an option; but it does seem to me like generating two values just for the sake of having two values. Although, given that data derived from the logger can never represent the same thing as data derived from live readings, I don't suppose it's any worse than the current situation.

[ejay]

Actually, no, I'm not using the option of "Use 'speed' for avg calculation". I only recently tried using the "Calculate 10-minute" option to try to smooth out the wind graphs, little did I realise (until now) that the disadvantage is the problem of calculating a 10-minute average from... er, a 10-minute data logger interval from my WH3081.

I suppose I could try setting my 3081 logger interval to 5 minutes or less, then the Cumulus 10 minute average would probably work properly with data downloaded from the logger.

[steve]

Actually, no, I'm not using the option of "Use 'speed' for avg calculation".

Yes, that's what I meant; the default is with that option not set, i.e. to use the 'gust' value for the calculation. With it set, the logger data should produce two distinct values; the 'gust' value, and the 'average' value calculated from the stations average value, i.e the same as the station's average value if the logger interval is 10 mins or more.