Relative powers
From PhotoVoltaic Logger new generation
Contents
If you have for example more than one solar plant/inverter with different size/orientation, the absolute power values in watt are not so helpful for comparison.
A common unit for comparison is kilo watt per kilo watt peak.
So therefor you have to transform the watt data from a power sensor into kilo watt per kilo watt peak.
Setup
- A power sensor (with unit watt in this example)
- A proxy channel for calculation
I use for this the calculator channel type, which is meant for such a use case.
To force the proxy to make the calculation, a proper resolution must be set.
- Inverter 1 installed power: 11.28 kilo watt peak
- Inverter 2 installed power: 9.18 kilo watt peak
Transform watt into kilo watt per kilo watt peak: 
Channel definitions
Values for the factor attributes:
- Inverter 1: 0.0000887
- Inverter 2: 0.000109
Build a proper channel hierarchy:
Chart
Now the channels are better comparable:
