TFA Nexus and UV-Index?

[Michael]

Hi,

I use the weather station TFA Nexus (35.1075). I am now interested in the value UV index. From TFA there is the solar wind sensor (30.3168). Unfortunately I find unclear information whether the wind sensor also transmits the UV index.

If someone uses this wind sensor here and can tell me whether the UV index is transmitted. If not, is there another alternative for the TFA Nexus in connection with a Raspi?

Many thanks in advance

Michael

[Andreas]

Hi Michael,

it is nearly a year now that you had this question, perhaps it is still interesting for you: As far as I know the wind sensor does not transmit the UV index. Years ago a seperate UV sensor was available, but it was fragile and it can't be bought any more.

Before I used weewx, the data of my TFA Nexus was collected and prepared by WsWin. With this software it is at least possible to calculate the sunshine with the difference temperature between the regular temperature sensor and the temperature of the wind sensor which is situated in sun. This worked quiet properly in my case and would have been absolutely sufficient e.g. for control of shutters.

Unfortunately weewx does not support this feature, or I did not find it yet. For sure it would be possible to create a new "virtual" sensor for this calculation, but the formula would not just have to calculate the difference temperatur, but have to consider season, geographic position, sunrise/sunset and so on. Not so easy ...

[Ton vanN]

Hi Michael,

TFA_Nexus definitely has no UV-sensor in the catalogue of interfacing sensors.
It is a bit odd, but the windsensor of TFA_Nexus provides a related temperature reading.

As indicated in the other response, you have to find the data related to light and to UV outside the TFA_Nexus.
Examples for light-values: programs WsWin and WeatherDisplay have 2 functions to get virtual light-values.
1) Modify a T&H-sensor by replacing the NTC-resistor for a LDR or for photodiode
=> resistance is a function of light-input
The software translates into a light-value. Accuracy is [euphemistally] very limited.

2) Solar-Jar is a Temperature-sensor in a glass jar. The sun heats the air in the jar (or not).
The difference between the temperature inside the jar and another thermometer outside the jar is a measure for the lightlevel.
;-) Do not talk about accuracy ......

The program WsWin has a wsmerge-function by which you can import UV-data into the set of sensors elsewhere (= outside TFA_Nexus).

Op maandag 25 februari 2019 18:06:40 UTC+1 schreef Michael: