Battery discharge to 2nd battery

Hi. We have 2x AC3.0 inverters each feeding 8.2KWh batteries…

As the sun time and PV generation increases each day now I have backed off the overnight off peak charge level from 90% to 55% to ensure we use all the PV and not export and since then the 2 batteries are constantly fighting for charge?… discharging rhe other one to achieve 100%?… each day it could be a different battery that takes preference… but they are not balanced at all?? Means we lose power through the inefficiencies of the inverters each day which is annoying? Is this the same ol firmware frailties with dual invertors?? Is this something other dual invertor installations experience?

I believe restarting one of the inverters (via the web portal, my inverter page) may stop it fighting. But you have to notice it to take action!

I think the EMS box is needed to properly sort it. That needs redevelopment to work with the new firmware.

Not sure if the beta software - which I believe is being rolled out now - fully resolves the issue.

We have the same setup: Twin AC3 each with an 8.2kW.h battery.

Occasionally they will do this 'cross-charging', but perhaps once every couple of days. If we spot this happening, we simply restart both inverters in the portal, and it stops. If you are finding that they are 'fighting' all the time then I suspect something is not right - most of the time they should play nicely together.

If you want some more feedback from the group, I suggest you post a picture of the energy graph, from the Portal. That will give us a much better idea of what is happening.

Here is mine, which shows a short cross-charge (i.e. blue both below and above the x-axis) at about 9:30-10:00pm:

ToothyChris Thanks for this..

I have never been able to drop an image into these forums?..Will try and get similar graph up onto the chat. Paul

Here are the two inverter files (if this works?). I cant work out how to combine them..

There's a cross at around 8am..

Also, looking at these graphs, I note that one inverter is only showing PV from 1 string that we have and the other inverter shows the other string?.. like they are separated...? not what I expected as the batteries and AC 3.0s were retro fitted to the PV installation?.. I thought they would see and share input from the TVs together - ie in parallel?

Hi Paul, well done on mastering the image uploads.

Rather than uploading graphs for the individual inverters, have a go at uploading the combined graph (like mine), as this gives us a much better overview of what your complete system is doing. This 'Power Graph' should be visible on the Portal home page (by which I mean the 'Dashboard').

Chris

ToothyChris - I am sorry I haven't been back to you to acknowledge your suggestion..This is I hope what you mean from todays graph

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Paul