i have an emonPi2, and have been intending to calibrate the power readings against actual meter readings, in fact, scale by comparing kWh in a given time. [I have already calibrated V against a multimeter, and phase angle correction for the various CTs.]
The Serial Config Tool page only gives the option to choose from a drop down list of CT types, not to do fine calibration of the CT value. I can do that using “k” commands in the config tool directly (e.g. k1 99.31 1.2), but then the CT types just display as blank. Is this by design? Am i trying to calibrate the wrong thing?
I don’t have an emonPi2 so I can’t check for you, but I suspect what you’re seeing is happening more by oversight than by design.
If you set the calibration directly as you have done, saved the values to EEProm and then listed the correct calibration constant, I think you can safely ignore the gaps in the Serial Config Tool’s display.
(If list doesn’t work for you, this appears to be another oversight I spotted recently, and which has also been seen by others and reported here within the last few days.)
Bear in mind both the c.t. and emonVs have a phase error which varies with the magnitude of the quantity measured, and is more pronounced in the c.t. I have the next version of emonLibDB which incorporates the ability to introduce a deliberate phase shift of 90°, which means you adjust for zero power factor rather than trying to find a very flat peak. This gives a very precise measure of the combined phase error. The library also included continual calibration using the precision voltage source for improved stability and accuracy - but the hardware suffers a design error. I stopped work on the library when it became clear that the problem with the wrong components wouldn’t be corrected.