I have a solar power installation with a 50A AccuCT on each of the two phases. I’ve noticed that the one phase consistently shows a larger power output than the other. This difference even persists at night, when the one phase indicates 0W, as expected, and the other one indicates around 5W. This morning I moved the CT from the phase exhibiting this strange behavior onto the other phase (i.e. both CTs are now on the same wire), and found that the difference in power measurements persists.
Can you think of any possible cause other than the CT being bad? I’d appreciate suggestions for troubleshooting.