Sometimes the system briefly imports from/exports to the grid, due to sudden changes in energy consumption.
As with all grid-solar-battery systems, the solar panels generate power during the day. This power is used firstly to support your household load, with any excess energy going to the battery.
If there is still solar after this, it will feed back into the grid. At times of high-power usage, or at night and on low-sunlight days, the home draws power from the battery and as a last resort the grid.
From time to time, when solar is being produced there might be a sudden decrease in household load when turning certain appliances off. As a result, the system might briefly export excess solar to the grid before charging the battery. This will only last for a short period of time.
Similarly, if there is a sudden increase in load, power might be imported until the system has turned on the inverter and adjusted to the increased demand.
We refer to these sudden changes as “spikes”.
This is normal system behaviour and is necessary for the long-term performance of the system.