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Overhead Cabling

LithiumGuy

Corralling Electrons
Joined
Apr 2, 2021
Messages
21
I'm located in California and need recommendations on electrical wiring to run an overhead/aerial cable.

I need to connect a solar array to the house mains which is on an adjacent and separate building. The overhead/aerial will be over 10ft high above ground and be across ~11ft gap. There will be a "messenger" steel support cable as is required by code. I need 12/3 conductors (two conductors + ground).

The cable can't be solid cable because it will look odd as it won't "hang" and be crooked. So I was thinking of SOOW cable that is super strong and yet super flexible as well as being fully UV and waterproof. But I'm reading that NEC code doesn't allow "flexible" cable to be mounted permanently? Perhaps they're referring to "flexible" as extension cabling? But SOOW is several grades of durability above "extension" wire cabling.

The other choice is UF-B outdoor cabling which is within code but I think it only comes in solid form making it odd to hang across a gap especially at 12AWG thickness.
 
Triplex neutral support cable is designed specifically for free air overhead spans, typically used in utility service drops, the neutral has a steel core for support, 12 AWG is unlikely available but having larger conductors won't have any negative impact.Screenshot_2021-09-01-19-11-03.png
 
Id say to follow code.

It should be supported by the steel wire using cable saddles of some sort anyways.

You should be consulting a local electrician for this, "uv resistance" does not mean outdoor rated either and you should be able to get the appropriate type of wire in a stranded version.

I like the self supported cable but it may not be code everywhere.
 
I found free access to NEC 2020 edition and Article 396 Messenger-Supported Wiring describes it all along with allowed cable types. Table 396.10(A) lists that good old MC-Metal Clad cable (armored cable) can be used for aerial (see attached page below).
MC will be excellent here because it will have natural smooth gravity induced bend you'd expect from an aerial line. I would end up just fighting UF-B on the messenger support cabling and it would still look somewhat crooked and bumpy despite best efforts.

I will also spray paint my MC cable's aluminum armor matte black to match the other aerial lines (cable TV & telephone). Being a very visible aerial overhead line, aesthetics is quite important!

NEC-Article396.png
 
super chill of you to share the NEC 2020 reference,
cheers ?

No prob! Yes, hopefully Google search will find this and help along others on the interwebs through the years.

Still though, SOOW cable would look the best aesthetically for overhead application. SOOW is smooth, super flexible and have a matte black covering already. I'm looking at the cross section of the SOOW cables I have and they're super tough. Several layers of tough fabric and rubber along with a thin woven metal jacket embedded inside. Its cabling markings indicate wet and sunlight resistant. Possibly SOOW may still be within code but I'll have to keep researching what the other generically listed cable types in Table 396.10(A) actually map to.
 
NEC allows it but your local code may not.

Also soow is sunlight resistant but not necessarily outdoor rated.

The stuff still dry rots in the sun over time. I've got an extension cord made out of the stuff that's spent far too much time outside and it's jacket is all cracked to hell, and definitely isn't water resistant anymore.
 
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