Service Entrance Conductors

[michael nye]

Article 310-8 (d) locations exposed to direct sunlight. States , listed or marked "sunlight resistant". Someone told me that thhn is not listed for such use, then what is ? I have been using it and have seen other installations a few years later and the thin plastic coat is hanging but the wire looks good, any help would be appriciated.

 

[paul]

Re: Service Entrance Conductors

THHN, THWN, THHN-2, THW, THW-2, RHW, RHW-2 and RHH are not sunlight resistant. USE, USE-2, SE and some UF (it will be marked) are sunlight resistant. I also noted that Essex, Southwire & others make sunlight resistant THHN in 1/0 and up.

There is also a very good write-up on it here

Goodluck

[ June 13, 2003, 08:15 PM: Message edited by: paul ]

 

[pierre]

Re: Service Entrance Conductors

Hello Paul

I am not trying to start a controversy here, but I want to rebut your statement.
That article is very good, but... did you notice who the gentleman represents.. The Aluminum industry...also he does mention part of his Abstract is his opinion.(maybe his company's opinion)
I have looked in the 2002 UL White Book, and it does mention that THHN/THWN can be listed for sunlight resistance.

Here is where I get kind of wishy/washy... I am not sure if the cable itself has to be marked. Maybe it just needs to be listed? I will call UL and post the response.

??

Pierre

 

[paul]

Re: Service Entrance Conductors

It sounds to me like it's just the drip loop that's in question, because it's exposed to sunlight. I never really though much of it before, but TW, THW, or SE should probably be ran in the mast for makeup to the POCO. I have seen THHN peeled and cracked away on several services in the past.

 

[bphgravity]

Re: Service Entrance Conductors

Type USE-2 with RHH or RHW-2 type insulation holds up very well too.

The sunlight here in SW Florida can melt the RMC riser!!

 

[james wuebker]

Re: Service Entrance Conductors

RHW-2 is shiffer than THHN but it is what I use also in this type of applications. It does hold up very well.
Bye now!
Jim