Solar Challenge - Can anyone identify these?

[Twoxentrix]

Thought replacing the old Solar panel(s) would be relatively simple - NOT.

Going to try keep this short, but also trying to clearly describe the issues :

Just pulled my old Solar panels off the roof rack and replaced them with one new one. I cut the wires on the old ones with the intention of soldering new updated connectors to the ends, and just plug into the new panel. But after unwrapping the plastic tube protecting the cables on the roof we came across a couple things we were not prepared for
First, The old system comprised of two Solara 55wt panels, and we discovered both cables from the old panels go down through the pop Top to the controller...obviously both were wired to the controller independent of the other. BUT, between the old panels and the controller we also discovered a 3" long metallic cylinder that is about 1/2" in diameter (one on each cable)...CAN ANYONE IDENTIFY WHAT THESE ARE? (I've been to two Solar places that mostly only do marine installations and none of the guys know - stated these were "before their time". My guess is older style diodes???



THE OTHER ISSUE IS the solar Cable that lead into these metal cylinders (from the old panels) have 3 wires on them, YET coming out the other end of the cylinder (the Controller side) are just 2 wires (a red and a blue, that travel to the Controller)...The new panel only has two wires in the cable. CAN I cut the old cable in the front of the cylinders (the side that has two wires, which is the controller side) and solder new connectors on there?

ALSO NEED ADVISE ON THIS: Since both the old 55wt panels were individually wired directly to the controller I fear the current wire is too small to handle the higher voltage of the new single 150wt panel. Without having to pull new cable, can i just double up on the wires and accomplish the same result of a heavier duty wire?

I'll include Pic's of the cut cable that has 3 wires in it (which were attached to the old panels), and the controller - if it helps any.
Thanks in advance for any help!

http://www.sportsmobileforum.com/for...cture35520.jpg
http://www.sportsmobileforum.com/for...cture35522.jpg

[Bbasso]

Personally I'd run new MC4 cables... and (rip out)not worry about the old stuff.
The more connections have the possibility of failure and poor current.

[BrianW]

Are you sure the mystery tubes aren't inline fuse holders? That would be my guess.

[Twoxentrix]

Originally Posted by BrianW

Are you sure the mystery tubes aren't inline fuse holders? That would be my guess.

At this point I'm not sure if they are "fuse holders". If it is a fuse holder, then I would suspect there would be a way to "open" them, correct? I will have to look more carefully because first inspection didnt reveal any type of twist lock mechanism...in other words i didnt see anything obvious

Also, any idea why the old Solar panel cable that goes into the "fuse holder" has 3 wires in the cable, and comes out the other end of the "fuse holder" with just 2 wires (the controller side)?

[Flux]

I would consider redoing the whole system, controller, wiring, and panel(s). The mystery cylinders with 3 in 2 out are like nothing I have seen on the market currently. That would bring into question the controller as well.

What controller do you have and what panel are you putting on top?? How were the two panels wired into the controller?? Parallel ?? Series??

[ShuttlePilot]

Interesting. I would agree without more info that they are diodes. When dealing with older used panels I have come across marine panels designed to be flush mounted and walked on that to be perfectly flat had external diodes. Although they didn't look like your picture.

Regarding using the old doubled pairs of wires for your higher wattage panel. That is possible but the practice of a double wire acting as one for increased capacity is a dark art of electrical engineering. It gets into resistance of each wire which can change due to age and connections on each, plus the fusible link resistance on each, field testing under varying loads to calculate, blah, blah, why isn't it performing as calculated, how much is a new single wire? You get the idea. It's generally only done when there is no other option.

I'd just go with running a new wire set, sized for minimal voltage loss. You only have 150 watts to get off the roof so wire wouldn't be too big but if your thinking of more panels at a latter time I'd go larger wire size and be ready.

-Eric

[arctictraveller]

I would definately start over and do it right the first time. Too many unknowns and potential failure points. Running new wire to a modern controller should not be that hard or time consuming.

[Scalf77]

I expect that they were a earlier version of these Solara Cell Protectors.

I agree with everybody else, just byte the bullet and run new wire. It probably might be a good time to upgrade the controller also.

-greg

[Twoxentrix]

Originally Posted by Scalf77

I expect that they were a earlier version of these Solara Cell Protectors.

I agree with everybody else, just byte the bullet and run new wire. It probably might be a good time to upgrade the controller also.

-greg

You may have something with this - The diagram also shows Solara has 3 wires going into the unit (which clarifies one of my other questions).

My new Solar panel (SunPower Semi Flexible Solar Panel 150W (ETFE+Aluminum) Photovoltaic - CA Sold | eBay) already has diodes included in the junction box that is mounted to the panel so i'll forgo this application, but I have ordered in-line fuses that i'll include with my install (thought that was a good idea).

Under the advice of all, I believe I'll replace the cable and possibly hunt for a new controller. Not knowing anything about Solar systems other than the obvious basics (converts Sun to voltage to maintain a charge), Is my current controller so out-of-date that it's obsolete? (installed back in late 2006). It has been operating fine.

http://www.sportsmobileforum.com/for...cture35522.jpg

If your responses suggest "yes", My challenge then is identifying a Controller that serves my purpose (preferably one that fits the original cut-out without having to do any additional modifications).

Thank you each for your input & advise.

[Bbasso]

I've been through 2 SCC and there doesn't seem to be a standard size, I had to make a new face plate for the second one.

Even with that negative the gains from a modern mppt solar charge controller will be worth it.