FoxESS Community - Owners & Installers Forum

Hi there, just got a Hybrid system installed and I can see from the data that the Grid consumption it reports is generally 3-5% lower than what my electricity provider reports I used for the same period.

A couple examples:
Day #1 Fox would report 17.0kWh consumption for a day while my bill would say I used 17.6kWh on the same day.
Day #2 Fox would report 53.5kWh, but my bill would say I used 55.1kWh

While I accept some difference I'm not sure if this is in the expected range, or whether there is some calibration that could be done to get this value closer.

It’s fairly normal, a CT clamp will never be as accurate as your smart meter, it will typically range between 1-5% depending on length of CT cable, proximity to other CT’s (for EV etc..) and it is worse at low loads.

You can replace the CT clamp with a directly wired meter such as an Eastron or Chint which tend to be nearer 1% accurate.