Service Drop Conductors

[Loffgren]

Advice needed....

This question applys to a residential home. The main service an exterior surface mount overhead fed 200amp panel with distribution. The main panel feds two interor sub panels. One of which has a riser up through the roof to a weather head and an over head fed to a garage with riser etc, then overhead again to a shed with riser etc.

My question: we are replacing the conductors on the overhead feed to the garage and shed along with other work. What type of over head conductors can i use. The lenghts of the spans are 40' and 30'. The circuit size is 50amps. I have looked at Triplex. Is there another code compliant conductor? Thanks for your time.

 

[augie47]

One other would be sunlight resistant UF used with a messanger cable.

 

[Pierre C Belarge]

If the THHN/THWN is listed as sunlight resistance, then one can use a messenger and the listed conductors.

See
225.6
310.13
Article 396

 

[Pierre C Belarge]

How many times do we see a conduit or tubing type riser outside for a service or application such as the OP's, with THHN/THWN installed and exposed to the sunlight before being spliced, such at the service point?

 

[Loffgren]

Thats what is there now and it has failed...

I belive triplex is the best way to go....agreed?

 

[augie47]

interesting question for this group :grin: when you say "triplex", a lot of red flags go up. properly rated ACSR would be a viable option. "triplex" as a 3 conductor cable would not work on a 120/240 circuit due to the absence of the 4th conductor. Utility "triplex" would not necessarily be permissible as it is often not a listed conductor.

 

[Loffgren]

Thank you, I was thinking I would have to install a gound rod at each.. I will look into the acsr

ACSR is a bare conductor correct? I dont see how that would work....

 

[iwire]

At this point most THWN is sunlight resistant

http://www.southwire.com/ProductCatalog/XTEInterfaceServlet?contentKey=prodcatsheet276

http://www.cerrowire.com/default.aspx?id=3180

 

[Loffgren]

re

re

Question, so by code i can use four THWN conductors for the span correct, limited to 50 feet without a messanger...??? 225.6(A)

Can i purchase a messenger wire?

New area to me forgive the ignorance...

 

[augie47]

Thank you, I was thinking I would have to install a gound rod at each.. I will look into the acsr

ACSR is a bare conductor correct? I dont see how that would work....

I was mostly just referencing your term "triplex". This forum is somewhat particular on terminology. :grin:Were I doing your job, I would likely install what I would incorrectly refer to as "triplex". I think to be proper "triplex" is simply one type of ACSR (aluminum cable-steel reinforced). I was trying to point out that (a) depending on your situation and Code cycle you might need an equipment grounding conductor (see 250.32) in addition to your ground rod and (b) some POCO aerial cable is not acceptable for NEC wiring applications as it is "covered" and not "insulated".

 

[Loffgren]

Ok i found some 6-4 ACSR

 

[LarryFine]

I . . . ACSR (aluminum cable-steel reinforced).

Minor note: If I'm not mistaken, the C stands for Conductor.

 

[LarryFine]

This forum is somewhat particular on terminology.

. . . ACSR (aluminum cable-steel reinforced).

Minor note: If I'm not mistaken, the C stands for Conductor.

Hey, you're right! :grin:

 

[Loffgren]

Can I use the uninsulated conductor as a ground and one of the insulated conductors as the grounded conductor?

 

[charlie]

ACSR is not required and it tough to cut. You can use AAAC (All Aluminum Alloy Conductor) if you can find it and it can be cut easily. That is all we use because we have had problems with the old ACSR steel rusting after the galvanizing let go.

 

[charlie]

Can I use the uninsulated conductor as a ground and one of the insulated conductors as the grounded conductor?

Yes you may. You will find that the conductors are marked with ridges to identify the different phases.

 

[Volta]

I know the triplex or quadreplex is used this way all the time, but is it made with conductors listed in T310.13(A)?

 

[Loffgren]

Thank you all, sure glad this forum is around...

 

[Power Tech]

I am only able to buy triplex and quadplex in min 500' roles.

Sugestion. Go to a temp power company and ask if they have some #1 scrap. Also you will need preforms and dead end clevises.

 

[Power Tech]

ACSR is not required and it tough to cut. You can use AAAC (All Aluminum Alloy Conductor) if you can find it and it can be cut easily. That is all we use because we have had problems with the old ACSR steel rusting after the galvanizing let go.

I have to look up the kind (leda?) I buy. Many different types with different ratings.

The one I use has a steel core that is hardened. 1/0 = 210 amps.