Charging 48v with 36v solar panel?

[dogdad11]

How did they do it? ...or did they?

Now that I finally got the '05 CarryAll II moving, I'm looking at the other stuff. Somewhere in its past, someone had stuck a big solar panel on the roof. Wiring goes to a little box with the label "ZFK-36 Intelligent Solar Controller" stuck on it. Coming out are 2 wires - one black and going to chassis ground and the other red with a battery-lug size terminal and just hanging there (so I don't know where it's supposed to go). I 'googled' the name and found no entries at all for it.

Probably won't be able to get to it for a day or two, but I'm really confused as to how it "might" have been connected to get 48volts out of it if it's only a 36volt charger. I don't see how charging 'most' of the batteries helps the ones that don't get charged with the solar unit. Or will they all charge faster when hooked to the wall, if some were charged with the solar?

Any suggestions?

[mrgolf]

Take the ground off the frame."no grounds to frame on electric carts". If you try to get this thing working the main pack neg is where that wire would go. Is the Panel still on the cart?

[dogdad11]

Thanks for the quick reply. And yes, the panel is still on the car.

I'll take the solar negative off frame and put it on the bat-pack. So's I can learn more, why no grounds to frame?

[Stevegrmich]

. .

[Sergio]

It is a safety thing, no systems over 24v can use chassis for ground, the amount of energy displaced in case of a short can be very dangerous.

Also, in golf carts in particular, the dissimilar metals used (aluminum, steel, etc...) will erode each other due to galvanic action if currents flow thru them.

In club cars with a working OBC, all negatives must go to the controller B-, not the pack negative. The OBC needs to account for all current being drained from the batteries for it to work properly.

[Sergio]

Originally Posted by dogdad11

How did they do it? ...or did they?
"ZFK-36 Intelligent Solar Controller" stuck on it. Coming out are 2 wires - one black and going to chassis ground and the other red with a battery-lug size terminal and just hanging there...
Any suggestions?

Just a thought, but that 36 may be referring to number of Cells, a 36 cell solar panel is used for 12v.

Perhaps it was charging an auxiliary battery? Measure the output of that controller when the panel is in full sun.

[dogdad11]

Thanks for the info and tips, guys. For such relatively-small and simple vehicles, these things sure are complicated. I'm getting a fast education from y'all, many thanks!

I remember my GrandDad always saying: "Be sure to learn something new every day".
Ok, I did, so now can I go back to bed?