As I started working on this patch I realized there's a problem with it: if some rain happens to fall in the few seconds just after midnight, we will lose its contribution to dayRain. This probably would not happen very often, but for the days when it does, the sum of 'rain' for the day will not be equal to the value of 'dayRain'.
I wish the downloaded LOOP packets had timestamps... -tk On Tue, May 30, 2017 at 12:29 PM, Luc Heijst <[email protected]> wrote: > Thanks Tom, > > This would be a solution for dayRain values received from the Davis LOOP > packets. I would opt for such change. > > BTW. What would be the maximum difference between the time stamps of > internal clock of the vantage console and the clock of the weewx computer? > I can imagine that in some cases the dayRain value would be reset to zero > BEFORE midnight which also could generate problems. > > Another thing. > I also receive Vantage Pro data from the meteostick driver which has no > "dayRain" data itself, so in this case weewx will calculate it somewhere. > I will check both dayRain loop message loggings round midnight to see if > the problem occurs only with the vantage driver. > If the dayRain values of the meteostick have good time stamps I might > consider to set the calculation to software for the Vantage driver, eg.: > > [StdWXCalculate] > [[Calculations]] > dayRain = software > > Luc > > On Tuesday, 30 May 2017 16:06:11 UTC-3, Tom Keffer wrote: >> >> The value of dayRain is from the Davis LOOP packets, which are, >> unfortunately, not timestamped by the Davis logger. The driver must add the >> timestamp. >> >> So, it is very much possible that the packet was created in the logger >> shortly before midnight, then weewx downloaded it just after midnight, >> timestamping it 2 seconds after midnight. >> >> I suppose we could change the driver so that it zeroes out the value of >> dayRain for the first packet of the day, provided that the time is within a >> few seconds of midnight. That violates our general philosophy of not >> messing with data coming off an instrument, but I can see good reasons for >> doing it. >> >> -tk >> >> >> On Sun, May 28, 2017 at 4:28 AM, Luc Heijst <[email protected]> wrote: >> >>> The meteotemplate uploader use value 'dayRain' to populate >>> meteotemplates 'R' value. >>> The template can send either archive data or loop data. >>> >>> When loop data is selected the 'dayRain' value is not reset to 0.0 at >>> the exact start of a new day but shortly after. >>> For my Davis Vantage Pro station I got recently in Meteotemplate a >>> registration of 29.0 mm rain with time stamp 00:00:02. >>> The result was a meteotemplate database value of 29.0 mm rain for the >>> first archive period that day >>> >>> Is there a solution for this in weewx? >>> >>> Luc >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "weewx-user" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- > You received this message because you are subscribed to the Google Groups > "weewx-user" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
