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From: KevinJ93 <kevin_es@whitedigs.com>
Newsgroups: sci.electronics.design
Subject: Re: Solar panels
Date: Sun, 2 Jun 2024 10:21:17 -0700
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On 6/1/24 8:32 PM, Don Y wrote:
> On 6/1/2024 6:29 PM, boB wrote:
>>>> Not sure how to avoid excessive charge currents into the battery if 
>>>> it can't
>>>> take the full solar output.
>>>
>>> I think you have to be able to "talk" to the module to tell it how 
>>> you would
>>> like it to behave, NOW.
>>
>> The MPPT controller simply raises the PV operating voltage above
>> Vmp...  At Voc, the current becomes zero. Whatever Vpv gives the
>> correct controller output voltage to the battery it is charging.
> 
> You have to signal to the controller that the battery is charged;
> that it can't (shouldn't) continue to accept charge.
> 

That will happen automatically when the battery reaches the set voltage.

Some of the charge controllers allow configuration for various 
parameters such as 100% charge voltage so that it will work with 
different chemistries.

In your case your load could be directly across the battery.

The one thing that is not obvious to me is how to limit the charge 
current if you use a small battery where the solar available could 
exceed the allowable battery charging current.

Maybe you could add a controllable dump for when solar generation 
significantly exceeds your load consumption?

kw