Emonpi and Huawei Lunar 2000 battery

I have recently had a Huawei battery storage system added to my solar PV system. I am having problems measuring total load on the house through my emonpi. When the battery charges over night the load does not register on emonpi, I don’t understand why as I am importing from the grid the same as any other load. Is it case of the CT clamp on the incoming live (brown) meter tail needing to be moved?

The setup has a separate inverter for the battery to convert A/C to D/C to charge the battery and then reverse to discharge the battery.

I am still registering a load when discharging the battery even though the inverter is maintaining a zero balance load as long as I don’t exceed the output of the inverter or the battery is discharged.

I setup my emonpi many years ago and haven’t had any issues. I know I would need an additional CT clamp to measure the battery inverter input/output, but I’m more interested in knowing when the battery is charging from the grid.

My initial reaction is that it isn’t doing what you think it should be doing.

If your setup is showing grid import at some times, it is working. The implication is your battery is discharging (so no grid import) when you think it is charging!

Can you check with your supplier what they think is happening (like Octopus shows half hourly readings).

Hi Brian,

That’s what I have been comparing it to, on smart the meter. I don’t get it as all feeds go in to a Henley block, and the Emonpi CT clamp and the battery CT clamp are on the tail that goes to the meter. So all power has to flow in or out of this cable. I’m pretty sure total load is correct just won’t count the battery charging load, and calculates I’m exporting when the battery is charging.

Hi Richard

If I’ve picked you up right, it sounds like your Emon Pi CT clamp may be the wrong way round if it is reporting export when you are in fact importing. Turn it round then run something briefly that will exceed your inverter/battery output to check that it registers the import - kettle and oven for example.

Hope that helps.


Worked it out, installer of the battery had moved the CT clamp on to a different line. :man_facepalming:t2: Thanks for your help.