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JP avatar image
JP asked

best/safest way to disconnect/reconnect lithium battery from solar

Hi,

I need to get access to behind the battery. The only way is to temporarily take it out. the battery gets charged from solar via a MPPT 100/30 as well as 230V charger and a DC-DC charger. I switch off the 230volt and the DC-DC only charges when the engine is on - that's fine. To disconnect the solar - here is what I plan to do.

1) put a blanket over the solar cells

2) turn off MPPT in app

3) do I still need to disconnect the wires from the solar cells?

4) then disconnect the battery

After I'm done reconnect in reverse - Is this correct?

Thanks

MPPT SmartSolar
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2 Answers
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pwfarnell answered ·

Your procedure looks good but in step 3 I would disconnect the solar panels from the controller for complete safety just in case your blanket blew away or slipped off. Then yes, when powering back up the reverse order, battery first then solar panels.

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Alexandra avatar image Alexandra ♦ commented ·
And maybe while everything is off adding a DC disconnect for the solar panels.
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JP avatar image
JP answered ·

Thanks for confirming my intended process is correct and safe. I see if I can add a switch between the PV and the MPPT input.

As a side note, I was just wondering what happens to the generated power from the PV when it's not needed (battery full and no DC use)? as the sun keeps shining and the power gets generated, where does it go?

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kevgermany avatar image kevgermany ♦♦ commented ·
Get proper solar isolator(s), made for the job.


When panels are disconnected or there's no load, there's no power. There's voltage, can be very high, but no current, so no power.


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