Inverter is over reporting the Grid Exports as compared to what Electricity provider is telling me

[grevox]

Hi,

I installed the Solar + Battery system a month ago and have been analysing the data over the past month and something feels off.

System details.

Solar: 13.3kw
Inverter: FoxESS KH10 (KH series, 10 kW single-phase hybrid inverter)
Battery: Make/Model: FoxESS EQ4800-L9, Total capacity: 41.93 kWh

I am with Amber (joined a week after the installation and joined their SmartShift VPP, still in learning mode).

I have Home Automation integration also with my system and I keep an eye on the data regularly to see if everything is ok.

I noticed a couple days after joining Amber that what FoxESS app tells me about the amount that I export to the Grid for that day does not match with what Amber is telling me. a little bit of difference is fine but the difference wht I have been seeing is huge.

I exported the inverter data for the past 10 days, got the usage data from Amber and compared the 2. Her's my findings.

Code: Select all

GRID EXPORT — FoxESS Inverter vs Ausgrid Smart Meter

Date         FoxESS (kWh)   Smart Meter (kWh)   Diff (kWh)   Ratio
2026-04-30          11.60                4.27        +7.33   2.72x
2026-05-01           8.50                3.11        +5.39   2.73x
2026-05-02           4.20                1.52        +2.68   2.76x
2026-05-03           8.40                3.10        +5.30   2.71x
2026-05-04           0.00                0.01        -0.01     —
2026-05-05          51.60               18.96       +32.64   2.72x
2026-05-06           2.50                0.91        +1.59   2.74x
2026-05-07           3.80                1.36        +2.44   2.79x
2026-05-08           4.40                1.61        +2.79   2.73x
2026-05-09          22.80                8.32       +14.48   2.74x
TOTAL              117.80               43.16       +74.64   2.73x

GRID IMPORT — FoxESS Inverter vs Ausgrid Smart Meter

Date         FoxESS (kWh)   Smart Meter (kWh)   Diff (kWh)
2026-04-30           0.30                0.23        +0.07
2026-05-01           0.30                0.20        +0.10
2026-05-02           0.20                0.24        -0.04
2026-05-03           0.20                0.23        -0.03
2026-05-04           0.30                0.25        +0.05
2026-05-05           0.20                0.16        +0.04
2026-05-06           0.30                0.26        +0.04
2026-05-07           0.30                0.23        +0.07
2026-05-08           0.20                0.23        -0.03
2026-05-09           0.20                0.19        +0.01
TOTAL                2.50                2.21        +0.29

The import numbers look perfectly fine but the export numbers are wrong. The inverter is over reporting the export numbers by almost a factor of ~ 2.73x consistently.

Something is wrong. I have asked my installer about this but also wanted to post here to see if others faced this issue what this possibly could be?

[CrazyGrayV8]

Hi, this looks really weird alright; can't be a coincidence that all of the ratios are basically 2.7x, surely. But what it all means...who knows.

Only advice I can think to do is see what the app vs meter panel shows is going to the grid once your battery is at 100% and there's some reasonable amount of kW coming off the roof. It's getting later into autumn obviously and the sun is getting low but I assume you'd still get about 9-10kW off the roof in a full sun / noon time...?

Then see what the app and smart meter show real time; one of them must be wrong...could be a CT clamp or something is not quite right or similar...?