Need Good Sources for Quality Bulk Solar Cable

[crcr]

I'm building a solar system on our TT. I am going to buy my own MC4 connectors, crimpers, etc, and build my own custom length cables for connecting the roof solar panels to the roof combiner box.

I'm having trouble finding quality 10 gauge UV-resistant cooper (not copper clad aluminum) cable designed to attach MC4 connectors to, in say 50 ft lengths (or where it can be ordered by the foot). Anyone have good source(s) to recommend for this? Sometimes I find some cable that looks good initially, but then find one or more reviews that state that the cable they received was 12 gauge, not 10 gauge.

Another question -- I'm finding both 19 strand and 7 strand cables -- what are the pros and cons of each (I presume that 19 strand is more flexible), and which is designed to work well with MC4 connectors?

Thanks for any input!

[Ed_Gee]

crcr wrote:

ktmrfs wrote:

Ed_Gee wrote:
Recommend this place for high quality solar materials:
AM Solar

x2.

Thanks. Nice looking wire, but two problems with it -- that is 10 gauge -- I'm looking for 8 gauge as mentioned in my last post. And even at that, this 10 gauge roof wire is pricey at $3 a foot plus shipping!

OK, but in your original post you said you were looking for 10 ga.UV protected wire, which is what my link took you to.
P

[crcr]

pianotuna wrote:
#10 is not big enough unless you are going to MPPT controller with a high voltage input. Even then you may wish to do #8 or #6.

Try Home Depot. You can select UV and gauge 6-2 or 8-2

Thanks. I'm using a PVM controller, so yeah, definitely want to run #8.

I already checked with my local Home Depot stores, and they do not stock UV resistant wire.

[crcr]

C Schomer wrote:
I redid my panel wiring last summer and I put any exposed wire in conduit. I also cut out all the plug connectors and crimped/soldered. One off those plugs easily pulled apart... Very poor internal crimp. Craig

What type of conduit did you use, plastic electrical?

[crcr]

BFL13 wrote:

crcr wrote:

BFL13 wrote:
I used ordinary #8 black and red, no UV. The red goes pink after a while if left exposed. I used plastic split wire sleeving over the exposed wires on the roof. No UV protection in that either AFAIK, but will replace when that deteriorates. If the 1991 RV outlasts that!

Thanks, yeah, I was considering doing just that! So you covered the wires with commonly available split wire loom?

Yes. I was able to pair the black and red #8s into one split loom from each panel. Can't remember size of loom , 1/2" ? Used Eternabond strips here and there to hold it down

A good lesson learned the hard way, is leave the panel pigtails to stick out past the panel when the panel is lying down. Now you can add your wire to that. It gets complicated if you have to add your wire to the panel first before laying it down, and then you can't get at it if your connection isn't connecting right.

Thanks. So what type of connections did you use from the pigtails?

[pianotuna]

#10 is not big enough unless you are going to MPPT controller with a high voltage input. Even then you may wish to do #8 or #6.

Try Home Depot. You can select UV and gauge 6-2 or 8-2

[C_Schomer]

I redid my panel wiring last summer and I put any exposed wire in conduit. I also cut out all the plug connectors and crimped/soldered. One off those plugs easily pulled apart... Very poor internal crimp. Craig

[BFL13]

crcr wrote:

BFL13 wrote:
I used ordinary #8 black and red, no UV. The red goes pink after a while if left exposed. I used plastic split wire sleeving over the exposed wires on the roof. No UV protection in that either AFAIK, but will replace when that deteriorates. If the 1991 RV outlasts that!

Thanks, yeah, I was considering doing just that! So you covered the wires with commonly available split wire loom?

Yes. I was able to pair the black and red #8s into one split loom from each panel. Can't remember size of loom , 1/2" ? Used Eternabond strips here and there to hold it down

A good lesson learned the hard way, is leave the panel pigtails to stick out past the panel when the panel is lying down. Now you can add your wire to that. It gets complicated if you have to add your wire to the panel first before laying it down, and then you can't get at it if your connection isn't connecting right.

[crcr]

BFL13 wrote:
I used ordinary #8 black and red, no UV. The red goes pink after a while if left exposed. I used plastic split wire sleeving over the exposed wires on the roof. No UV protection in that either AFAIK, but will replace when that deteriorates. If the 1991 RV outlasts that!

Thanks, yeah, I was considering doing just that! So you covered the wires with commonly available split wire loom?

[BFL13]

I used ordinary #8 black and red, no UV. The red goes pink after a while if left exposed. I used plastic split wire sleeving over the exposed wires on the roof. No UV protection in that either AFAIK, but will replace when that deteriorates. If the 1991 RV outlasts that!

[crcr]

ktmrfs wrote:

Ed_Gee wrote:
Recommend this place for high quality solar materials:
AM Solar

x2.

Thanks. Nice looking wire, but two problems with it -- that is 10 gauge -- I'm looking for 8 gauge as mentioned in my last post. And even at that, this 10 gauge roof wire is pricey at $3 a foot plus shipping!

[ktmrfs]

Ed_Gee wrote:
Recommend this place for high quality solar materials:
AM Solar

x2.

[Lwiddis]

10 gauge wouldn't be my choice for long runs. 7 feet is the max for 10 amps with a 2% drop WindyNation says at https://www.windynation.com/jzv/inf/choosing-right-wire-size

[crcr]

Thanks for all your replies. Much appreciated.

I just got to looking at the wire leads with MC4 connectors on the solar panels I just bought, and I don't think the wire is even close to 10 gauge, seems smaller. So now I'm thinking that maybe I'll just un-solder those pigtails from the junction boxes on the solar panels and as someone here suggested, solder in my own wires to the combiner box. Therefore no MC4 connectors needed.

So if I do that, I'm thinking that I would prefer to just go to 8 gauge wire. But I'm having some difficulty finding 8 gauge UV resistant copper wire in bulk, say 50 ft rolls. Any suggestions as to where I could buy 8 gauge UV resistant copper stranded wire reasonably? I've checked on the sources mentioned, and so far didn't find any.

[time2roll]

I would buy some MC4 extension cables on amazon with connectors already attached. Cut in half with the connectors to the panel and the cut end in the combiner box.

Even better with panels in series and skip the connections in the box and pull the MC4 direct to the controller.

[Tom_M1]

If this is a permanent install you don't need connectors. Just wire direct from panel junction box to combiner box. Any connector will add a bit more resistance to your run. If connectors are needed, I would suggest using Anderson Powerpull SB50 connectors. The contacts can be crimped or soldered.

https://powerwerx.com/anderson-sb-connectors-sb50-50amp