I noticed that my ‘Feedback Extra DC PV to Grid’ stops each time my battery reaches 100% SOC. From data gathered is when CCL drops to 0 my MPPT’s stops producing power.
I was under the impression that if the Feedback Excess DC PV to Grid is enabled that it ignores this setting.
My current setup is GX 3.41 fw, Freedomwon managed battery and 2 x MPPT’s. Below a graph showing when my Battery reaches 100% SOC and the effect on grid feedback. Is there a setting that I am missing? DVCC is using the default forced ‘off’ values with now additional settings set. All shared settings are Off and no limit on battery voltage or current.
No one having any ideas?
I’ve now made a video of what happens. After a few MPPT firmware downgrades I got the RS450 to play nice but the 150/35 is still dropping to near 0W when CCL is set to 0. The link below is a video clip of what happens, with all the latest firmwares both RS450 and 150/35 Grid Feedback drops to ~0W when CCL=0 even though Feed excess DC PV to Grid is enabled.
Notice the CCL change from 0A → 15A → 200A at ±1:30 into the video and the small 150/35 on a 1kW array coming back to life.
Check the charge voltage requested by the BMS, and the actual voltage of the battery. You have a FreedomWon Lite (I assume), which has a dynamic charge voltage. If the charge voltage is raised by the battery, then there is no more overvoltage to feed into the grid, and the Multi will stop doing it.
FreedomWon batteries don’t typically drop the CCL to zero. They lower their charge voltage instead.
The BMS will typically lower the charge voltage quite drastically at the same time as it lowers the CCL, which will account for the sudden spike of feedin right afterwards. I think this triggers a large discharge which lowers the battery voltage quite fast, and then it takes a while for the battery to develop enough of an overvoltage again to start seeing an excess to feed in.
Take a look at what your CVL does during that same time period. I bet it is dropped dramatically and then slowly jacked up afterwards, so that it takes a while before the overvoltage feedin mechanism kicks in again.
(IE… this is normal… not ideal, but normal).
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You are correct, I do have a Lite and the CVL also drops during this period. Here is what VRM shows for the same time period. My measurement on HomeAssistant looks at the modbus register of the BMS here
PS. CCL does drop to 0A unfortunately.
