l'm back after a few years

[augiedoggy]

Originally Posted by coosa

I'm bumping this thread about the solar charger to see if anyone has any advice for me; Augie, are you still around?

So the cheap mppt controller worked fine when I hooked it up to the cart and the 100 watt solar panel. It somehow sensed that the cart was 36 volts and kept it at around 40 volts while the sun is shining. Since it drops to nothing at night, I thought that should do a good job of keeping the batteries topped off while I'm not around.

But then I got to the farm yesterday and the controller read 46.1 volts, which is a higher charge rate than any 36 volt charger I've ever had. I tested the pack with my meter and got 45.5, but the meter has always read a little lower than the controller.

That seems to be way too high, especially for a charger that is always on in the daytime. I'm afraid it's going to boil the batteries with that much current.

Is my concern valid, or will it not hurt anything? I realize this isn't the sort of thing that most golf cart guys deal with, but I'm hopeful someone has some solar experience and can advise me. I guess my only options are to keep letting it charge , or just do away with the charging system. Thanks for any ideas.

What voltage did you set the controller to charge to? You have to program them to charge to the specific voltage you want. At least thats how the 3 different boost charge controllers I have work. I agree 46v is high for a 36v battery pack.

[coosa]

Originally Posted by augiedoggy

What voltage did you set the controller to charge to? You have to program them to charge to the specific voltage you want. At least thats how the 3 different boost charge controllers I have work. I agree 46v is high for a 36v battery pack.

Thanks Augie, but look at my post earlier about the controller they sent me. It was NOT the one in the description on Amazon, but a much cheaper model. There is no adjustment whatsoever to it, nothing to set at all. It said it was self adjusting.

My other controller for the house batteries will cut off if all the batteries have a full charge, but I have some old batteries in the string and it seldom cuts off. I've never seen it get above 13.5 volts even in the brightest sun, but it hardly ever cuts off the current, probably due to the old batteries.

But still, keeping those batteries charged up with the solar panels has given them incredibly long life. There's a Walmart marine battery in the string that has a 2011 tag on it, and it still works.

The longevity I've gotten from those batteries is what made me decide to try to on the cart. Maybe it won't hurt it, but I don't know. I'm thinking the safest thing to do at this point is to junk this controller and buy another one that I can set.

[leapingbuddha]

................thanks .l just used 12 volt panels ...worked great for me now l need info on lithium batteries........3 x 12 or one 36 volt....again l am no rich just handy.....

[Capt. Lenny]

DIY your own lithium and $ave! It's not that hard, more intimidating than anything else.