Three phase upgrade leads to milliwatt readings on branch CTs

Support
#1

Ahoy!

I’m running an IoTaWatt here in Sydney, Australia and after completing our three phase upgrade and Solaredge install (2 inverters, I think A and C phases) I’m struggling to understand what has happened to the branch circuit monitoring. I have reasonably expected numbers on my three 100A mains CTs, but since derived three phase all the branch circuits appear to just report noise? There are at least 500-1000W loads on the GPO circuits and I have a pretty good idea of the layout but I have no feedback at all to start figuring out which branch is which when everything is reading zero?

Apologies for the screenshot spam incoming.

IoTaWatt install

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Rebuilt board, an absolute mess but apparently these are “gold class” electricians. It’s a travesty.

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CBs and bus bars.
Note: In this image the VT is connected to the bottom most protected power circuit labeled “4”.

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Single phase historic data

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Now - Three phase derived

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CT setup
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What am I expecting? Since the majority of the loads were rewired onto phase A (All GPOs and lights in case of AC coupled battery) I should have at least half of my branch CT’s reading correctly without phase discovery for the other CBs.

I feel like I’ve missed something very obvious but I’m struggling to see what I’ve done wrong.

#2

I agree, but seems to be pretty normal down there. I have no idea what any of that is, and don’t think I see any mains CTs in the picture, which is what I would be interested in to begin with. I understand your feeling that there should be little difference between your old single phase and the three-phase, but apparently there is - or you really didn’t use any energy on those circuits during the 12 hour period.

My advice would be to treat this like a new three-phase install, and go through the procedure to get your mains configured and working to match your meter. The rest should follow on pretty well from there. The procedure is here.

Graph+ is not the best tool to use for setup. The status display is more useful.

#3

Ahh that’s my fault for using a picture from when they were halfway through the install.

Both the IoTaWatt 100A CTs and the SolarEdge CTs are on the supply side of the service fuses well upstream of the board.

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Agree on the status page being more useful. That’s been what I’ve used to align the A,B,C readings with the SE numbers. That part makes sense, why my branches are all zero is less so.

Could I be seeing this type of issue if the VT phase is wrong? Should I reset the IoTaWatt to single phase and see if the GPO branches start making sense again then repeat the process?

#4

The most straightforward way to resolve this is to follow the recommended procedure.

#5

I’ll try again and let you know. Thanks @overeasy