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scaarup avatar image
scaarup asked

MPPT ve.direct ground problems

Hi.
I have added a small esp-board which is connected to the ve.direct port of my MPPT controller. This board can read data from the MPPT and send it home to me. The problem is, that my solar panels are not working when I set things up like below. I the MPPT reports some error about ground bypassing the MPPT. So I suspect it is because the ve.direct ground pin, is connected to my battery's ground. But how can I else accomplish this? Can I isolate it?


Thank you.


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MPPT ControllersVE.DirectGrounding
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3 Answers
wkirby avatar image
wkirby answered ·

In these cases where there are grounding problems, the it's best to use a digital isolator. Something like a SI8422 will be a good one. Use the 5V pin from the VE.Direct conector of the MPPT to power that side of the SI8422, then use 3V3 or 5V from the ESP side to power that side of the isolator.

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scaarup avatar image
scaarup answered ·

Awesome, that sounds like what I need.
Do you have other examples, like this component? Can't seem to find one, at my local arduino/electronics store...

Thanks

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rin67630 avatar image
rin67630 answered ·

Don't connect the ground from the VE interface, only the ground from the battery.
I hope you have a buck converter to reduce the battery voltage to 5V.

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