FAQ: Difference between revisions

1,152 bytes removed ,  27 November 2013
→‎What do the various wind speeds in Cumulus correspond to, with Fine Offset stations?: - simplified, this entry had too much unnecessary information added which made it hard to follow
(→‎What do the various wind speeds in Cumulus correspond to, with Fine Offset stations?: - simplified, this entry had too much unnecessary information added which made it hard to follow)
Fine Offset sensors measure wind over 48-second intervals, divided into 24 2-second intervals. At the end of each 48-second period, they transmit the highest of those 24 values as 'Gust', and the average of those 24 values as 'Wind'. The console keeps writing the newly received Gust and wind values to the same area of console memory every 48 seconds, until the station logging interval time is reached, then it moves on to the next memory location, leaving the last values it wrote in the previous console memory location.
*If Cumulus is not running all the time, on restart it works through the console memory locations and extracts the Fine Offset Wind and Gust in each memory location, i.e. at the station logging interval.
*IfWhile Cumulus is running all the time, it reads the console memory storedcurrent wind speedspeeds (and direction) every 10 seconds into the arrays <#wspddata> (and <#wdirdata>). Note this means that some values are duplicated, there are new values only every 48- seconds.
 
Cumulus, for various reasons, uses different terminology, and also has configuration settings which control how some of the wind values are displayed.
* The Fine Offset console 'Gust' value (every 48 seconds if Cumulus is running, or at every station logging interval if restarting) becomes Cumulus 'Latest'.
* The highest of the above Fine Offset 'Gust' values over the previous 10 minutes becomes Cumulus 'Gust'. (If Cumulus is restarting and station logging interval is 10 minutes or greater, Cumulus Latest and Cumulus Gust cannot be properly differentiated).
* Cumulus 'Average' can be calculated in 3 different ways:
** The default: If 'Calculate 10-min wind average' is not selected on the Station Settings screen, the console 'Wind' value is used.
** The average of the 24 2-second sensor measurements (Fine Offset console 'Wind' value) becomes, if Cumulus is running with default settings, Cumulus 'Average'. (If Cumulus is restarting, then it uses the subset of these available at the station logging interval).
** If 'Calculate 10-min wind average' is selected, then by default the average of the Fine Offset 'Gust' values read over the previous 10 minutes is used.
** All Fine Offset 'Gust' values read over a 10 (configurable by adding ''AvgSpeedMinutes=N'' in [[Cumulus.ini#Section:_Station]] where 'N' is number of) minutes interval are averaged to become Cumulus 'Average' if in the ''Settings'' frame of the '''Station''' screen in the Configuration menu, you select ''Calculate 10-min wind average''. (If Cumulus is restarting and station logging interval is that number of minutes or greater, Cumulus Latest and Cumulus Average cannot be properly differentiated).
** If 'Calculate 10-min wind average' and 'Use speed for avg calculation' are both selected, the average of the Fine Offset 'Wind' values read over the previous 10 minutes is used.
** All Fine Offset 'Wind' values read (if Cumulus is running) over a 10 (configurable by adding ''AvgSpeedMinutes=N'' in [[Cumulus.ini#Section:_Station]] where 'N' is number of) minutes interval are averaged to become Cumulus 'Average' if in the ''Settings'' frame of the '''Station''' screen in the Configuration menu, you select ''Calculate 10-min wind average'' and also set the next option ''Use 'speed' for avg calculation''. (On restarting, dependent on station logging interval, there may not be multiple values to average).
 
== How do I set up recording wind speeds in Cumulus, with Oregon Scientific and La Crosse stations ==