CT installation direction

DIY
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1

I have a multiplus II setup for ESS.
The system is grid tied and has a 3P75CT meter as the grid meter.
The meter manual says to install with arrows pointing from source to loads so I installed it pointing from source (grid) to load (main service panel). That seems right to me, but 98% of the time when I look in VRM it doesn’t make sense and appears to show the grid meter backwards I think. When I think I should be exporting to grid due to AC coupled PV generating 3kW and home is low and I would expect usage to be 200-300W, instead of showing usage at 250W or so and a roughly 2.7kW export to grid as I would expect, I see energy usage of around 5.7kW and grid usage of 2.8kW or so. I would guess I installed CT backwards but have checked a half down times. Or did I and in this case is this system the source and the grid the load?
To top it off, once or twice a day for a few minutes when I check it all looks good and the grid meter shows what seems reasonable.

Can anyone confirm that grid meter CT arrows should point from grid to home, and assuming I got it right, does anyone have any ideas what is going on here with the backwards value?

2

Direction can also be subject to incorrect wiring?

To test put large load on ( greater than what mp is set to supply)and see what is reported, if export reported then ct wrong way.

3

It’s not just about proper wiring. Please check the settings. It is set to grid meter or for example PV Inverter?

6

Do you have a 1-phase or 3-phase grid connection?

You didn’t mix the CT wiring so that Ln isn’t over the corresponding phase wire?

Are you using a VE.Can or Ethernet connection?

Did you update the firmware already?

What is Settings → ESS - → ‘Multiphase regulation’ set to?

Could you please add a screenshot of your meter settings?

8

Hello and good morning Sir. Ah. Split phase. I forgot about that option. Oops. So used to 1 and 3 phase installations :grimacing:

Anyway. Seems like that the orientation of your CT’s had to be changed :crossed_fingers: Ran into this issue myself many times. Sometimes it is really difficult to picture what setup people have. Without schematics and/or pictures of the actual setup and wiring.

Have a nice sunny day :raising_hands: