Any field mapping in the driver is considered the default or starting point 
- it should provide something that works for most users. Any [[field_map]] 
entries in the [GW1000] stanza overwrite/replace the default map contained 
in the driver. Any [[field_map_extensions]] entries are used to alter the 
default field map in use (whether that be the default field map from the 
driver or the field map specified in the [field_map] stanza). So any field 
mapping in the driver should not be overwriting any field mapping in 
weewx.conf.

Hopefully the linked driver wiki pages make sense of the Ecowitt solar 
radiation related fields available via the API and driver. When I wrote the 
driver my aim was to map data from the Ecowitt API to equivalent field in 
the WeeWX schema where they exist. The only direct equivalent was the 
Ecowitt 'uvi' value which is mapped to the WeeWX UV field (UV index). The 
Ecowitt API also provides a value referred to as 'uv' with a range of 
values from 0 to 65535 microwatts per square metre. This is clearly not 
solar irradiance as solar irradiance typically ranges from 0 to 1500 odd 
watts per square metre whereas the 'uv' value ranges from 0 to jut 0.065535 
watts per square metre. So 'uv' was passed through by the driver as 
'uvradiation' (could not use 'uv' as that would be confused with the 
existing WeeWX UV field). The final field provided by the API is referred 
to as 'light' in the API documentation and is measured in Lux. There is a 
commonly used approximation for solar irradiance given a light value in 
Lux, but it is not the place of a driver to calculate such derived 
parameters. That is handled better elsewhere in WeeWX, hence in the linked 
wiki page you will see reference to adding a calculation for WeeWX field 
radiation in the [StdWxCalculate] section of weewx.conf.

It's messy and not really intuitive, but there is no simple solution here..

Gary
On Tuesday, 4 February 2025 at 08:12:23 UTC+10 Harry van de Laar wrote:

> Regarding the 'uvradiation'field: I noted that in gw1000.py, the 'uv' 
> field is mapped to 'uvradiation' . I can imagine this would be 
> overwriting/blocking the fieldmap extension in weewx.conf.   Anyway, 
> changing the mapping in gw1000.py, results in a radiation values in the 
> data base. 
> Indeed my question is, is it the correct radiation. Thanks for the 
> suggestions you made, I will go in to the details.
> Thanks
> Harry
>
> Op maandag 3 februari 2025 om 21:19:02 UTC schreef gjr80:
>
>> Reply received via email - for future replies to weewx-user posts could 
>> you please use the '*Reply all*' button rather than '*Reply to author*'. 
>> '*Reply all*' posts publicly on weewx-user avoiding my spam filter 
>> discarding your 'post', let's someone else chime in if needed and most 
>> importantly maintains a public record of the issue to aid others in the 
>> future.
>>
>> Unfortunately your log extract truncated the entire WeeWX startup so 
>> there is no detail on the WeeWX configuration. Please try again, if you are 
>> following the instructions previously linked make sure you start the 
>> capture of the log before you restart WeeWX otherwise you will miss the 
>> WeeWX startup.
>>
>> The debug report looks fine. There are a few extractor entries under 
>> [Accumulator] in weewx.conf that don't appear to make much sense 
>> (uvradiation, 
>> rrain_piezo, erain_piezo, hrain_piezo, drain_piezo, wrain_piezo, 
>> mrain_piezo, yrain_piezo), but they will not be the cause of the problem.
>>
>> That being said I suspect that you do not actually want to use the 
>> uvradiation field. I note in your original post you want to facilitate 
>> plotting of radiation and ET. In that case I suspect you will be wanting 
>> to use the light value from the gateway device to approximate solar 
>> radiance rather than the uvradiation field. You will find further 
>> background on this in the Ecowitt gateway device driver wiki FAQ page 
>> <https://github.com/gjr80/weewx-gw1000/wiki/Frequently-asked-questions> 
>> under '*My Ecowitt station has a light sensor on my station, but I don't 
>> see WeeWX field radiation. Where is it?*' The linked page *Understanding 
>> Ecowitt LAN Wi Fi Gateway API radiation fields 
>> <https://github.com/gjr80/weewx-gw1000/wiki/Understanding-Ecowitt-LAN-Wi-Fi-Gateway-API-radiation-fields>*
>>  
>> also provides further background and instructions for approximating solar 
>> irradiance.
>>
>> Gary
>>
>

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