question

mfred68 avatar image
mfred68 asked

How do i start manual equalisation?

I have a mppt 450/100 , I installed it 3 days ago along with a small make shift pv array of 1600w.

I have a 42kwh lifepo4 4 battery bank, that's 6 x 7kwh batteries in parallel.

Today the whole system shut down because there was no sun and the soc was halted at 15%, but later that day I noticed that one of the 6 batteries had powered off due to being a much lover soc than the other 5, this is making me think I need to do a manual equalisation?

When I first set up the mppt, I remember it giving options to equalise manually or every 30 days. I chose 30 days, but now feel I should equalise now, but the equalisation is greyed out. How can I equalise them now? I dont remember disabling these options and i cant find how to enable them.1000038820.jpg

MPPT Controllersequalisation
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2 Answers
Justin Cook avatar image
Justin Cook answered ·

You don't - LFP batteries must never be equalized, and that's why the option is greyed out.

You mean balancing, and that should be being handled by the batteries' BMS unless the bank is wired so oddly -or the charge profile isn't set correctly- that the BMS can't work with what it's being given.

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mfred68 avatar image
mfred68 answered ·

Thanks for that info. I had expected the 6 battery banks to have balanced themselves, by simply being connected in parallel, I'm surprised they don't.

I did earlier balance them manually by charging all 6 from the grid and waiting for the first battery to advance to the next led indicator, then disconnected that battery, then waited for the next battery to advance to the same level led soc indicator and disconnected it, and so on. Now they all show 2 out of 4 leds illuminated indicating 25% soc.

Is this a recognised method of manually balancing the batteries, or should this method be avoided?

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