In your screenshot a red message “Alarm: E-Manager ungültiger Wert” appears, so something is still wrong.
When Lambda configured my Modbus-Access they configuered it to
E-Meter Messpunkt: E-Eintrag. So in my case sending positive values is appropiate:
@nullen.js: In my posted configuration above I put it in the read-part, that was wrong. You have to put it into the write-part. That seems to work: When openhab sends a negative value, the heat pump shows 0 kW.
Das Skript:
(function(inputData) {
if(inputData < 0) return "0";
return parseFloat(inputData) ;
Ich musste dazu als Add-on Javascript in Openhab (Installed automation Javascript scripting) ergänzen, das Skript sitzt in /etc/openhab/transform