50Hz/60Hz phase measurements


The new phase measurements are coming along well. These phase measurements are not intended to be definitive of the various CTs in general, just their performance when used with an IoTaWatt and 20 Ohm burden resistors.

In general, what I look for is a relatively flat low shift curve. The purpose of all this is to calibrate the phase correction, but at the end of the day, the smaller the correction required, the better. So having CTs with basic shift that match well with the VT shift accomplishes that. I’m happy to report that most of the Echun CTs available at the Stuff site are below 1°.

I have two samples of each CT, so these graphs show the shift for each at both 50Hz and 60Hz.