Need pics. Also, any info on the equipment you can provide. (make, model)

I did some level of reverse engineering. Seems that the panel has two power + leads and 1 neg (ground) lead. The battery is hooked up with some 14 gauge 2-2wire romex. The white (ground) is hooked to the negative terminal and the positve is hooked to a fuse block. Anyway, here is what I think is going on. I only have one remaining question.

the blue lines are the externals. All the black are internals. To make it true to reality, I added a separate ground line to the ground side of the panel. This actually attaches to a ground block in the controller box.

My question is two fold. 1-What if the right hand fuse on the panel goes, but the right one does not? Then there will be no voltage to the charge controller. 2-how can the charge controller work? it has to charge when the battery needs it and cut off the charge when it does not. the only lead to the CC to the battery is shorted to the panel voltage. How can this ever read the battery voltage? If the battery charge is sensed, how can the charge be shut down? Does the charge controller simply short the panel (and battery) to ground? The wires aren't big enough to take Isc.

Anyway, I think Ifigured out the external feeds, but I can't figure out how the CC actually works. I don't know what the model is, but I looked it up on google and had no manuals or hookup diagrams.

What do you think, Rod?

rod,

there are two black and two white leads from the CC. Both whites go to a common block where I suspect everything else is ground. The blacks are as shown--1 from the panel and 1 from the battery. I think it may have some charge-sense timer, perhaps a capacitor in the CC. Something like (pseudocode)

check panel voltage w/ lead 1
check battery voltage w/ lead 2
if voltage is available AND if needed,
CONNECT LEAD 1 TO LEAD 2 (charge duration may be a function of discharge state)
else disconnect Leads.

what do you think?

the clarification I can give:

the two leads from the + side of the panel go into fuses mounted in a siemens J-box, JN321.

The charger itself is a "smart Charger" with a subtitle of "20 amp PV charge controller" made by APT-Ananda Power Technology.

dunno if this helps, but maybe? I suspect that the second lead from the panel (inner loop) should not even be there. Then the panel could work like I hypothesized. I realize that it could not work as it was.

If you can find out something about this, I'd be etermally grateful, If not, could you at least suggest a way forward? maybe put a VOM on the leads from the pamel to make sure it's making some Juice?

Thanks.

Peter

Well, I dug and I dug, and looked all over, and I can not find anything on this APT Smart Charger anywhere. I feel like I've been on the hunt for Nessie!!! But I have thought a bit more about it. I'm nearly sure that the solar panel's + and - leads should connect to a white and black on the controller. Meanwhile, the other two leads from the controller go to the battery + and -. What I am concerned about is two things. 1) There is no distinction between which leads go to the panel or battery, and 2) It'd be unusual for a DC component to use black for + and white for -. It's quite possible the whites should be + and the controller switches the -.

It's to the point where I'd almost have to open the controller and study the board to make a firm decision. All above is strictly assumptions.

LOL, yes, it's frustrating. I agree with you about omitting the inner loop in your diagram. The only thing I think I might also change, is not tying the panels negative to the ground. (not that it shouldn't work that way)