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#25513 - 05/11/03 04:57 AM Wire Insulation
electrician02125 Offline
Registered: 02/01/01
Posts: 89

What are guys using for service drop wire?

The installation I'm working on is directly exposed to sunlight most of the day and by the looks of the old service coming out I need to worry about resistance to the elements.
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#25514 - 05/11/03 05:25 AM Re: Wire Insulation
sparky806 Offline
Registered: 12/07/02
Posts: 59
Loc: Shawnee, KS, USA
The "service drop" is supplied and installed by the poco. The "service entrance conductors" on the other hand are installed by the EC. I use THHN.
#25515 - 05/11/03 05:39 AM Re: Wire Insulation
sparky Offline
Registered: 10/18/00
Posts: 5303
the 'ol sunlight resistant 310.8(D)

note 'marked' vs. 'listed' there....

anyone care to comment on quadriplex URD 3 ph risers?
#25516 - 05/11/03 08:51 AM Re: Wire Insulation
Electricmanscott Offline
Registered: 01/12/02
Posts: 1457
Loc: Holden, MA USA
Do you mean the drop to the house or the riser on the house. The drop is supplied by the poco and is whatever they feel like installing at the time. For the riser I use triplex aluminum run in pvc. In Mass there is no requirement for sunlight resistant wire for drip loops.
#25517 - 05/11/03 09:50 AM Re: Wire Insulation
electrician02125 Offline
Registered: 02/01/01
Posts: 89
"Service entrance conductors" is what I am asking about. From weatherhead down to meter socket.

THHN doesn't do very well in direct contact with sunlight. I have seen many an installation where the clear cable cover (not insulation) is falling off from exposure to the elements. Do they make a sunlight resistant THHN?

Thanks for the replies
#25518 - 05/11/03 10:16 AM Re: Wire Insulation
caselec Offline
Registered: 04/14/02
Posts: 558
Loc: San Jose, CA
Using THHN for this application would be a violation since THHN is not rated for wet locations. I would have to admit that all of the THHN I have seen is rated as THHN/THWN but make sure you are using THWN. I pretty much gave up using CU THHN/THWN for any thing #2 and larger quite a few years ago and switched to XHHW. The insulation on XHHW does not start to fall apart within a couple of years after being installed when exposed to sunlight and it also holds up much better in underground application. Many of the high tech company's and schools in my area will not permit any THWN to be used for underground applications.

E-Scott - Why did MA decide not to adopt 310.8(D)?

Curt Swartz
#25519 - 05/11/03 11:35 AM Re: Wire Insulation
iwire Offline
Registered: 01/05/03
Posts: 4391
Loc: North Attleboro, MA USA
For the most part MA. has a common sense approach to the code, if something has worked for years without trouble they will not make a change.

We can still feed down to a switch using the white of two wire cable and return on the black.

Qualified people know this, so why change now.

We also have a less restrictive derating chart we use for more than 3 current carrying conductors in a raceway.

We use the NEC with about 70 to 80 changes to it.

Bob, South of Boston, MA
Bob Badger
Construction & Maintenance Electrician
#25520 - 05/11/03 06:08 PM Re: Wire Insulation
harold endean Offline
Registered: 02/16/02
Posts: 2233
Loc: Boonton, NJ

I met Shawn ( or Shaun?) From CES the other day. He said that he knew you and now he met me. He is going to be the foreman on the next big building here in the complex. I then ask Gary if he knew you. He said, Yes. I then started telling him stories about how you want me to watch over him to make sure that he doesn't screw up. Then after goofing with him for several minutes, I told him how we know each other on this web site. They are doing a terrific job down here and they are moving along quite rapidly. That is the name of the game sometimes, hurry up and get it done.

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