Gonna post my 400A Split Service beta experience here one more time with the latest data, mostly to share the main moral for Sense usage - Always close your CTs completely
I installed my additional CTs for dual panel on 5/26 and let them go for about a week, only to discover that my dual panel Sense hourly reading was consistently below my utility reading by about 2.5%, or almost 4.5% if I took out a couple EV charging datapoints. I popped into my main breaker box, rejiggered the newly installed CTs on 6/3 and waited a while to rechart. After the CT adjustment, my dual Sense data was essentially dead-on with my utility data on an hourly basis with very little scatter.
Here’s the unity plot of Before and After the CT change.
And here’s the histogram of the error vs. my utility reading, both Before and After. The ideal, of course, is a tall vertical bar right at 0, kind of like the After portion.
Moral of the story - when you install your additional CTs, make sure they are completely closed !