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ron-bentham avatar image
ron-bentham asked

Should solar be switched off when 220v charging is in use?

This question has been on my mind for ages - and now I have a nice new Victron 12/30 charger, it's about time I resolved it!

Traditionally I was always led to believe that in a situation where multiple charge sources were available - ie solar, 220v and engine - it was OK to leave them all connected, and the battery would just take its charge from wherever it could.

But these days everything is digital, and both my Epever solar controllers and now my new Victron charger have charging profiles - so I am now worried that if 2 digital charge sources are always present, being switched on and off randomly, and load being taken out of the battery, also randomly - which is basically how a boat or motorhome installation works ... won't all the algorithms fight each other, and result in confused charging cycles?

Basically I have a choice - connect and forget, or manually switch - it wouldn't be a hassle for me to disconnect solar when 220v is present.

Some expert guidance would be welcome.

Thanks

battery charging
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3 Answers
Kevin Windrem avatar image
Kevin Windrem answered ·

As long as the total charging current does not exceed what your battery bank can accept, you are OK to have multiple charging sources active at the same time.

You should do what you can to match the profiles of the various chargers if possible.

If chargers aren't matched, one will enter absorption or float before others, so the bulk charging current will be reduced. This may increase charging time but won't hurt anything.

When DC loads pull energy out of the battery bank, the voltage will eventually drop below the float threshold resulting in bulk charging. The bulk charging current will supplement the battery in supplying the DC loads. This too is good.

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ron-bentham avatar image
ron-bentham answered ·

Many thanks. That's interesting and informative.

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Paul B avatar image
Paul B answered ·

Also further to Kevin,s reply, its important if you are using Lithium Lifepo4 batteries as the BMS must be able to turn ALL charging off if a cell voltage goes high, so please make sure that the BMS can turn ALL charging off if needed,

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