Ha Vincent! Nice to see you again 
I got it working yesterday buddy, thanks for your input nevertheless here and in the other topics and likewise to @Josar, the Double.parseDouble(valTester)/3600 did the trick for me.
Now… The result 
Vermogen = Power
Spanning = Voltage
Stroom = Current
Fasestroom= Current of Phase L1
Third time’s a charm and I’ll be creating a new topic for the persistence in InfluxDB and Grafana, because weird enough everything for KNX and all the other stuff works like a charm and I thought that adding these SMA values to InfluxDB would be a matter of adding the right group tags but that would have been too simple in OpenHAB 
. It’s sunny again (very partly cloudy) in Belgium after a couple of grey days so I’m very curious too get some values.
Oh, the “Dagopbrengst EUR” (day yield) is based on the “Dagopbrengst kWh” and is just a multiplication of Wh * 0.0000709 (7.09 eurocents / kWh)