Pulling energy from the grid for no need?

Hi can anyone shed some light in this for me , my solar system is a few weeks old only, and after it was commissioned the installer warned me that the grid would show some small wattage going into the house sometimes ....his explanation was this wattage was coming from the CT clamp and it was basically a false reading and the design of the clamp causes this. this was fine for the first 4-5 days where the house drew o.o48kwh or there abouts ....but now we're drawing sometimes 180w and sometimes 89w what seems to be constantly and the energy from the grid for the past 4-5 days has been 1.35kw a day which is backed up by the octopus energy usage graph .......for example right now the solar is producing 493w ....the battery is 96% charged and sending 200w to the house ...but the grid is sending 98w to the house ......why is this , why doesn't the battery just send 298w and the grid nothing ? thanks Steve

I've had similar issues to yours. I would start by checking the wiring connections between the CT clamp / EM115 meter and inverter. If the cable between the EM115 and inverter is wired using CAT5 or similar data cable you should check they have used a single twisted pair. Dont expect zero import 100 percent of the time though.

SteveRobinson I wouldn’t worry about it too much. The CT clamp is not 100% accurate and what you are seeing is an instantaneous reading from the inverter and the inverter is constantly balancing solar, home and grid demand to minimise your import.
You can’t really see this on the app as it only samples every 10 seconds on local or 5 minutes on remote monitoring.

The other thing that’s happening is as the battery gets close to 100% full, some of the cells within the battery will already be at 100% and others may be say 90% so the inverter will slow down the rate of charge to topup the battery to 100%.

If you look on your Octopus smart usage graph you’ll see most of the imports are tiny tiny amounts. The inverter has a reaction time so if you turn on a high demand appliance (kettle, oven, etc) the is a tiny lag as the inverter recognises the demand and rebalances pulling from the solar or battery to supply that demand.
You may well also see occasional large spikes of grid usage. These are where the house demand exceeds what the inverter can supply and the balance has to come from the grid. Depending on which inverter you have it will have a 3.6kW or 5kW max current draw so if you turn on the oven, washing machine and kettle at the same time the total house demand may be say 7kW and the inverter can only supply part of that, the rest coming from the grid.

Thing is my usage for octopus on the app is 1.5kw or 1kw per day .....so it would seem I am pulling from the grid for ne need

Thing is my usage for octopus on the app is 1.5kw or 1kw per day

Not sure if these numbers make sense, If its 1kWh consumed in a day then that would be 60p.
The point here is that it is small and should be such a small percentage of your overall consumption.
The Inverter, as mentioned before, takes time to balance between PV/Battery/Demand/Grid...and one of the slowest is switching from battery charging to discharging. While this happens the power has to come from somewhere to satisfy the demand and that will almost certainly be the grid as its instantaneous power.
Another reason the time to balancing of power that the inverter needs to do, is the synchronise the frequencies and phase to the grid. They have to be correctly timed and tracked to ensure there are no issue in injecting power from the inverter.

I don't see that you have any issue and is probably within the working parameters of the system, assuming your numbers are correct and my calculation/assumption is correct.

SteveRobinson Why not post your energy graph from the portal so we can see things a bit more clearly.