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PW2 Reported Grid Export on 3-Phase


New Member
Apr 9, 2018
Berkshire, UK
I have a single PW2 on a Gateway2 in a 3-P house. The PV is on 3-P Inverter and the car charger is 3-P.

Now we are into less sunny days it is becoming more obvious that the Tesla App and API reported "Grid Export" figures seem to be incorrect. For example yesterday the App says that 1.8kWh was exported to the grid and 46.2kWh was imported. At no stage through the day was the PW2 full so it should have been able to mop up any PV generation over consumption and we certainly didn't exceed 5kW generation at any point.
In addition the PV diverter car charger also reports house grid export which it says was 0.1kWh - but lets say zero!

I just wonder whether the Gateway is properly accounting for the "phase balancing" it must be doing through the day - ie exporting on its phase to compensate for imports on the other phases - which is what I understand it does.

I wondered if there is anyone else in the UK or elsewhere with a similar 3-P setup? My installer I believe knew what he was doing with the various Gateway current sensor placements and I haven't noticed any other anomalies. We only recently moved to a working (at least until recently) 3-P Smart meter so I don't have any useable data to compare with to see if it "thinks" there is any net export going on.

It is a bit OCD I know but I would like to know whether or not we are really exporting or not (we are on deemed 50% PV export anyway so that isn't affected anyway).

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