[movax]

I’m having a similar issue on one of my subpanels where I have solar present; hoping that when I move the Emporia to its own breaker, it might help.

One thing though… you mentioned you set your solar multiplier to just over 1.x. Is your solar 120 V, or 240 V w/ two lines out (assuming North America). If you have a CT on only one of the lines out from the solar setup, that multiplier should be 2. I have one CT per line from my PV setup (in hope that someday we can combine circuits), so Solar L1 and Solar L2. I have every single circuit in my sub monitored and still have a mystery balance going on… which leads me to suspect some weird setup / accounting issue.

Other than that though, maybe a CT is connected, but the direction is swapped (so not measuring a load) or some other issue is happening… your Vue is convinced that the main clamps are measuring just over 1 kW and that it can’t find the missing power when it adds up all connected CTs.

[movax]

Got a better antenna for the Vue out back, so installed the third one out back and still having some odd issues…

* I had some very weird behavior where the rear subpanel Vue would record a very large balance amount… which shouldn’t be possible as I have every circuit monitored by a CT. There are 2 2 pole breakers and 1 single-pole, so I installed 5 CTs (in the vain hope that some day Emporia will push a SW update that allows for combining circuits).. Hot Tub L1, Hot Tub L2, Solar L1, Solar L2, Service Receptacle. I confirmed all the CT orientations — the mains K->L pointed to the panel, Hot Tub/Service Receptacles pointed to the loads, and Solar L1/L2 pointed back to the panel.

* So, I power-cycled it and now Solar L2 is missing… how does the Vue determine if a CT is connected or not? I piggy-backed the Vue off the Solar breaker, and now I’m thinking this might lead to it getting confused. Ordering a pair of tandem breakers so I can get the Vue off on its own connection.

* In the initial setup of the Vue, when it asks if I have solar or not, and to toggle it on/off… do I have to re-run this on each Vue? Or just the one that has solar directly attached to it?

[movax]

CTs are passive devices; they shouldn’t induce anything into the lines you are monitoring. If the errors started happening after you installed the CTs, chances are a wire may have been jostled loose / moved around in such a way that you’re seeing these errors.

[movax]

Thanks for the detailed reply — makes sense to me. My fundamental misunderstanding / misconception was that for a given CT channel on a Vue, it is not bipolar / it is not able to measure current in both directions, whether because of a hardware limitation in how the ADC circuit was implemented, or if it was a solar load. So — my data right now is useless because even if the hot tub is off, and solar on and producing 2-3 kW, that’s going to be tracked as 2-3 kW of load.

I’ve seen conflicting posts on whether to flip the CT or not on a generator load (end up with two negatives cancelling out sort of thing); if you flip the CT *and* mark the load as generation / solar, will it count the direction correctly? Or do you only do one or the other?

[movax]

This would be awesome to have… if you have spare CTs, measuring both legs is nice to make sure there isn’t an unbalanced load downstream.

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