Windchill calculation from second temperature sensor

[markhiseman]

My WMR100 has a combined wind and temperature sensor. A site that is good for a wind sensor is not so good for an accurate temperature, so I have added a second temperature sensor (th1) in a better location.

I have set up th1 to be the outdoor temperature and humidity sensor on all the relevant Meteohub pages, and this shows up OK on Weather Display Live (WDL).

However, the windchill reading in WDL is still based on the original temp sensor (th0).

Is it possible to have Meteohub calculate windchill based on the selected temp sensor (th1), not the original sensor (th0)?

Thank you - Mark.

[opa38]

Bei meiner Cresta wird mir auch die Winchill Temperatur am windmesser angezeigt. Leider greift Meteohub diese Daten nicht ab. Das heißt, man kann den Außensensor als relevanten sensor in Meteoub nicht auswählen. :(
Das finde ich auch schade.....gerade der Vergleich von Temperatur am Windmesser mit anderen Temperatursensoren ist sehr reizvoll.

[EmjayNet]

Did you find a solution to this?

I have an identical setup to you, but have recently increased the height of the WTGR800 to about 30ft, like you I find the temperature at this height is way out compared to ground temperature. So added an extra THGR810 for ground temperature/Humidity.

But I wanted to make WD take this new sensor as the main temp/hum/chill for display & record purposes.

I couldn't find any way of doing this in WD or any where that would also resolve your problem.

Seems a shame as you can do this sort of thing in WD if you use the USB connection but not for Meteohub!
You can also select what sensors data you want to send to weather networks but not what sensor data sent to WD!

[markhiseman]

I'm afraid not :( .

You CAN use the new sensor as the main temperature and humidity sensor by selecting the relevant sensor on the various Meteohub option pages.

However Meteohub won't let you use it for the windchill calculation it seems.

A shame as you say, but Meteohub is otherwise great!

Mark.

[EmjayNet]

I can not find any way to do this without having to import it to WD.

I've got a similar question on the WD board but no answers.

Seems silly that something so simple can't be done.

[markhiseman]

With Winter approaching, could I raise this request again?

It looks like this feature has progressed, since the Weather Station menu now includes a Windchill Calculation dropdown selector.

However with my WMR100 the only option offered is 'compute from wind + th0 reading'. Could I ask for 'compute from wind + th1 reading' to be added as an option (for those who have an additonal temp sensor attached)?

Many thanks,

Mark.

[EmjayNet]

I don't use the WMR100 anymore I'm now on a VP2+ :)

But I would change the additional sensor to be the TH0 and the one in the wind vain to be TH1. this way you get wind chill at ground temperature.

With v4 you can swap the sensor nubers on the sensor page.

[markhiseman]

Lucky you :)

I gave your suggestion a try and it looked great (windchill correct at last!) until I saw that it completely mucked up my temperature records!

My historic th0 figures are from the inaccurate sensor (even today it's reading 10 deg C above actual) and of course swapping the good sensor onto th0 means Meteohub recalculates all my WDL records using the 'bad' historic th0 data.

I've swapped it back, and I'm hoping Boris can accomodate my request.

Thanks for the tip though - it nearly worked!

Mark.

[EmjayNet]

Just a through Mark,

How about using the 'Calibration' feature on the sensors page to reduce your actual THO readings down by the right FACTOR, up until the date you switch the TH0 & TH1.

It will never be "dead on, balls accurate" :ohmy: but it will be in the ballpark and with then allow you to make the switch.

[markhiseman]

Good thought but no: I think the sensor is faulty and it doesn't have a factorable correlation to the right temperature. Trouble is, as you know, it's part of the wind sensor which works fine.

I'm wondering if I can use something like Notepad to do a global search and replace on the raw data files to swap my th0 and th1 readings in the historical data. I might try that when I get time.

Mark.

[markhiseman]

I think I have fixed this issue at last :)

EmjayNet suggested mapping my new temp sensor (which I had mapped as th1) into th0 using the Sensors menu. For new data this was fine, and if I had done this as soon as I added it to my system all would have been fine.

However I have been running the new sensor as th1 for almost a year, so swapping it into th0 meant that all my records were then recalculated using the 'faulty' th0 data from the old sensor.

I fixed the records problem (I think) by this method:

1. Stop all data logging/data uploads on Meteohub.
2. Back up all the monthly 'raw' data files from Meteohub to my PC. These seem to be text files.
3. Take a copy of the 'raw' files and use MS Word search/replace tool to swap all th0 and th1 records in each raw file.
4. Copy the edited 'raw' files back to Meteohub.
5. On the Sensors menu, map my new sensor to th0 (and the old one to th1).
6. On other menus, select th0 as the main temperature/humidity sensor.
7. Restart data logging/data uploads on Meteohub.

This morning, Meteohub has finished recalculating the weather data records and all seems to be fine: records are calculated from the new sensor ... and my windchill is correct at last! :cheer:

I hope my editing has not affected something else I have not found yet. :unsure:

Thanks to EmjayNet for that good suggestion.

Mark.