I am using a Vantage Pro 2, and I had forgotten (if I ever knew!) that the solar radiation value had a slower update rate than most other weather values, but it is certainly another reason not to worry about processing every LOOP value separately. You could even argue that (for this hardware) the LOOP code should accumulate time until the reported radiation value actually changes (or until an appropriately set maximum time elapses) before processing the previous period's values.
On Sunday, June 5, 2022 at 12:33:47 PM UTC-4 [email protected] wrote: > I think it is also OK to do an average for every 30 seconds. It depends > also on the weather station used. > For instance, a Davis Vantage Pro 2 ISS transmits an updated solar > radiation value every 50 to 60 seconds. So with this weather station, even > a 1 minute average would not be very different since anyway the solar > radiation values of the LOOP packet are the same for at least 50 seconds.! > > Le 5 juin 2022 à 18:02, 'Peter Fletcher' via weewx-user < > [email protected]> a écrit : > > I chose to average the LOOP radiation readings and only to do the > threshold calculation and make the sun/no sun determination every 30 > seconds because I thought doing it on every LOOP might overload LOOP > processing (I am running weewx on a Pi 3B, which is also doing a few other > things which use the CPU). If this is an unnecessary concern, as it may > very well be, your modified code is much cleaner than mine. > > On Saturday, June 4, 2022 at 12:41:08 PM UTC-4 [email protected] wrote: > >> It is a very good idea to calculate the sunshine duration for each LOOP >> packet and sum these values to make the final archive sunshine duration. I >> have modified my script accordingly : >> https://github.com/Jterrettaz/sunduration. >> The logic is the following : for each received LOOP packet, the >> radiation is compared to a calculated threshold. If the radiation is above >> the threshold value, the sunshine time for the LOOP packet is equal to the >> time elapsed between the previous loop packet and this packet (most of the >> time 2 seconds with a Vantage Davis Pro). >> The final archive sunshine duration is the sum of all the LOOP value >> within the archive period. >> Le vendredi 3 juin 2022 à 21:59:36 UTC+2, Peter Fletcher a écrit : >> >>> That makes some sense when you are getting data from an 'external' >>> sensor, though there are (IMHO) simpler ways of doing it. weewx already has >>> access to the LOOP radiation data from the VP2, so handling the processing >>> and data storage within weewx makes more sense to me in this case. >>> >>> On Friday, June 3, 2022 at 3:24:23 PM UTC-4 vince wrote: >>> >>>> On Friday, June 3, 2022 at 11:17:00 AM UTC-7 Meteo Oberwallis wrote: >>>> >>>>> if the interval of Weewx and the data logger is set to 10 minutes, I >>>>> would have liked to read the value of the solar sensor every minute and >>>>> then write it into a separate .sdb database as possible sunshine. >>>> >>>> >>>> Personally I'd use an external program called via cron and posting a >>>> message to a MQTT topic. Have weewx subscribe to that topic to get the >>>> data into your db. >>>> >>>> This is how I used to get my DS18b20 temperature sensor data into weewx. >>>> >>>> > -- > You received this message because you are subscribed to a topic in the > Google Groups "weewx-user" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/weewx-user/19ylVTRqbh4/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/weewx-user/0e631671-0a74-4963-9f1c-e5f81bc7c366n%40googlegroups.com > > <https://groups.google.com/d/msgid/weewx-user/0e631671-0a74-4963-9f1c-e5f81bc7c366n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > > -- 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/weewx-user/72776a59-cc07-4bd3-9fa2-382bb45b73c5n%40googlegroups.com.
