Argument with my bro

[Greg Kowieski]

This is for anybody.

So, I'm not an electrical guy at all.  But I've been reading a ton and I was explaining how the SBMS0 and DSSR20 do such a great job of battery maintenance AND you don't have overhead from and Inverter if Its off while you are charging on a cloudy day.

At which point he said.  Well, if its too cloudy, it will drain your battery if the panel voltage is less than the battery voltage.  

Now, I stared and stared at the schematic, and to me, it looks like the Diodes would prevent the "drain".

And of course, I would LOVE to tell my brother he is WRONG WRONG WRONG... 

Please tell me I'm right....  😁

[Dacian Todea]

Greg,

There will be no draining of the battery in cloudy day or at night.  With a typical 60 cell 260 to 340W panel you can expect about 1.5kWh in a sunny day and at least 0.1kWh in worse overcast day (dark snowy winter day).

If solar PV panel was to be connected directly to battery then at night there may be a very small 5 to 15mA of current flowing to the panels so say it was winter and night is 16h with a 26V battery that will be 4 to 6Wh much less than 100Wh it will produce minimum during the day so battery will never be discharged if all you have connected is a solar panel.  Of course the DSSR20 has an ideal diode build in so there is no current flow back to panel at night that was example for panels directly connected to battery that is not allowed anyway as you need a way to stop the charging.

[Greg Kowieski]

And what I hear is... I WAS RIGHT and I WIN!!!!!   Thanks Dacian,  You're the best!

[Sander van Berkum]

Im curious how much crates of beer you won with this bet :)

Op maandag 3 mei 2021 om 12:02:01 UTC+2 schreef Greg Kowieski:

[Jhon]

Your bro is right of course, even a 1 mW a day drain would make him right, although your bro offered me a beer to write this ;)

[Greg Kowieski]

NO!  he cannot be right this time.  I OWN this one!  Don't take this away from me.  I think we need to introduce the term of immateriality in this argument. 😎

But, here are two beers to bring you back to my side.🍻