With OH4, what’s the recommended way of doing calculations against two or more things to produce an item? I’ve got a few places I’d like to do this, but the obvious one is to use humidity and temperature data to calculate dew-point. These are separate channels (for me, this is separate topics from…

[image] Generating derived weather calculations with the Weather Calculations Binding Bindings Hi All, During the course of writing a binding for the WeatherFlow SmartWeather series of weather stations, it occurred to me that some of the data presented by weat…

You will have to use a separate Item for the dewpoint, use a rule to calculate the value and update the Item from there.

As you have both, temperature and humidity information, available in the same mqtt thing, you can calculate the drew point in a script transformation and add it as a channel to your mqtt thing. The script transformation will receive the entire mqtt message, needs to extract temperature and humidity…

Looks like the Weather Calculations binding is the only way to go here. Each of my MQTT entries have a subtopic, so there’s no one single message JSON that I can run through a parser and cherry pick multiple entries.

Multi channel calculation

Setup, Configuration and Use Items & Sitemaps

glhopital (Gaël L'hopital) November 19, 2023, 9:40pm 3