Question on MPPT charge controller for solar

[brundl3fly]

Hi there,

Trying to hook up a 48v MPPT charge controller up to my TXT. Understanding that a panel that fits on the roof will not supercharge the batteries, just looking for a little boost over time while it sits out.

The problem is the controller may be faulty but I did want to check with some smart people here before I get too deep in this. The panel is correct because there is an LED that lights when it gets direct sun. No problem there. There is another LED and a small panel that's supposed to light up if correctly connected to a battery. This does not work and is my issue.

I'm not that versed in battery series but it seems that I'd hook one wire up to the positive where all the other red wires are connected and the negative to the final post in the series where all the grounding wires are. Nothing else makes sense to me but since it's not working I thought I'd check.

Anything else you suggest?

Thanks for any help.

[Dwalls]

Originally Posted by brundl3fly

Hi there,

Trying to hook up a 48v MPPT charge controller up to my TXT. Understanding that a panel that fits on the roof will not supercharge the batteries, just looking for a little boost over time while it sits out.

The problem is the controller may be faulty but I did want to check with some smart people here before I get too deep in this. The panel is correct because there is an LED that lights when it gets direct sun. No problem there. There is another LED and a small panel that's supposed to light up if correctly connected to a battery. This does not work and is my issue.

I'm not that versed in battery series but it seems that I'd hook one wire up to the positive where all the other red wires are connected and the negative to the final post in the series where all the grounding wires are. Nothing else makes sense to me but since it's not working I thought I'd check.

you may also want to check for fuses inside the controller if not accessible from outside.

Anything else you suggest?

Thanks for any help.

If i understand what you are saying then yes, you can verify that you are on the 48v terminals with a hand held volt meter and are seeing 48v give or take.
You may also want to use your hand held volt meter and see what voltage that you are getting out of the solar panel itself when in the sun, pay attention to pos and neg, i recently got a longer set of cables for a solar panel and plugged them in found out that they were made wrong and the red wire was actually the neg and it would not work in my charge controller until I swapped the leads.

Hope this helps

[brundl3fly]

Thanks DWalls, I will check the battery pack voltage and the leads coming from the controller to see if I get anything.

[brundl3fly]

Battery voltage from the pack was normal using the battery posts I did. Under shop lights the solar panel showed a nominal charge using the meter and the red and black leads are marked correctly.

So no display on the controller (even in direct sunlight) but it does seem to be functioning... not much more to it than seeing a charge going out to the batteries I guess.

I had fairly low expectations due to panel size and inexpensive MPPT controller but this has managed to come up sort of those anyway

[Dwalls]

You may check inside the controller for fuses that may be blown, i wish that it worked for you because I was thinking about the same thing as ours will sit in the direct sun some of the places that we go, like Talladega in the fall. I may just get a 36 or 48v mppt and do a temp setup to see what it will do.

[Sergio]

The 48v on a MPPT description usually indicates the input solar panel voltage not the output voltage to charge batteries.

Do You have the model # used and is it connected to the proper battery voltage for the display on the MPPT to work?

[WalterM6]

What wattage is your solar panel?

[BobBoyce]

I had good success in the past with a "solar roof" charging system. I mounted 3 panels (connected in series) to a frame that I installed in place of the roof. It was much longer and a bit wider than the original cart roof. I did not use an MPPT charge controller. I installed an analog ammeter on the front bottom edge of the roof which indicated charge current. It worked so well that I packed the charger away and relied upon the solar to keep the cart charged over the next few years. I eventually put the original roof back on and sold the cart with the original charger. I still have the solar panels, now being used on one of my arrays.

There are such a wide variety of panel voltages/currents available today, which were not so availble back then, that you can build a much more efficient system these days. Especially with a lithium pack, which eliminates the need for the electrolyte stirring of flooded lead/acid batteries. A pair of decent capacity monocrystalline or polycrystalline (avoid amorphous, really low efficiency) panels and a simple on/off charge controller to prevent overvolt condition would be easy to set up. Cost is about access to the panels at a good price. I buy at below wholesale, typically well under 50 cents per watt. I paid 58 cents per watt surplus pricing for new satellite grade 325W panels that are slightly better than 25% efficient. Those deals are few and far between, but they do pop up from time to time.

Bob

[cgtech]

I agree, solar can be done with minimal equipment (equipment that uses most of the solar panel's power), and can be fairly effective. I never charge any of my batteries "from the grid". But, they aren't used to "play golf" either. Just keep them maintained. I have made some solar tops, they weren't much amps, but, lower amps equals lower equipment requirements. My boss has a cart that rarely sees a typical plug-in charger, and his has nothing more than a diode "regulating" it. Granted, he uses "the best core batteries around" for his, and he never used it for "18 holes", just yard duty, messing around, and kids riding it. He says "as long as it doesn't get drawn down to 'nothing', solar keeps it up awesome". He has a identical panel I use to keep any batts full. I currently only use my panel to keep everything ready and full, not cycling.