Type of insulation

[jeff48356]

At the Home Depot in Knoxville, they sell two kinds of service cable, both requiring conduit. One is for 200A service, which includes two 4/0 AL for hots, and one 2/0 AL for neutral. The other kind is for 100A service, and I assume is used mainly for underground subfeeds because it includes a green conductor. But it has three #2AWG and one #4AWG green.

My question is, what type of insulation do these conductors have? (XHHW, RHW, etc)? I know it's not THWN because that's the shiny type that's found on branch circuit copper conductors.

 

[Dennis Alwon]

All the se cable I have seen uses xhhw. It should be written on the jacket

 

[jeff48356]

OK, thanks. That's what I thought. And according to NEC, up to five such #2AWG conductors will fit in a 1-1/4" PVC conduit, so I should be good there.

 

[Dennis Alwon]

OK, thanks. That's what I thought. And according to NEC, up to five such #2AWG conductors will fit in a 1-1/4" PVC conduit, so I should be good there.

Jeff is this jacket cable or is it USE cable? If it is USE then the conductors may thwn-2

 

[GoldDigger]

OK, thanks. That's what I thought. And according to NEC, up to five such #2AWG conductors will fit in a 1-1/4" PVC conduit, so I should be good there.

When looking at raceway fill for a cable or cables, you have to take into account any filler and the outer jacket, so you need to find the OD of the cable in question instead of adding up the conductors inside it and using the tables.

 

[jeff48356]

There is no jacket; these are just four conductors twisted to form a set. The 200A set has three conductors; no separate grounding one.

 

[Dennis Alwon]

The 4 wire cable sounds like what we call trailer cable which I believe is RHW. Make sure it has some writing on it like Rhw because if it is truly an urd cable then it cannot be used indoors.

 

[ron]

I've seen cables that have conductors without named insulation on the individual conductors. It could be anything.

 

[GoldDigger]

I've seen cables that have conductors without named insulation on the individual conductors. It could be anything.

So there is no jacket so noplace to label things there and no need to label the individual conductors since they are part of a cable? Sounds like an invitation for an inspector to fail the installation if it is covered by NEC rather than NESC.
At a minimum the insulation type should be on the data sheet from the manufacturer. If it is not, then it is probably NESC cable for use by POCO and not technically suitable for use where NEC applies.
One example of this is the URD cable type mentioned earlier. Unless multiply labelled, it simply is not an NEC-recognized wiring method, whether used indoors or out.

 

[ron]

So there is no jacket so noplace to label things there and no need to label the individual conductors since they are part of a cable? Sounds like an invitation for an inspector to fail the installation if it is covered by NEC rather than NESC.
At a minimum the insulation type should be on the data sheet from the manufacturer. If it is not, then it is probably NESC cable for use by POCO and not technically suitable for use where NEC applies.
One example of this is the URD cable type mentioned earlier. Unless multiply labelled, it simply is not an NEC-recognized wiring method, whether used indoors or out.

I've seen NM cable with no insulation labeled on the individual conductor insulation.

 

[Dennis Alwon]

Wires inside a jacket are not labeled such as NM cable but this cable is labeled if it is compliant. Our trailer cable is a 4 wire twisted cable that has RHW on it.

 

[Dennis Alwon]

Here is a Home depot pic. This is from Southwire and they (home depot) call it URD

 

[Dennis Alwon]

This is the page from Sothwire so I am not sure what type of insulation it has. It may not be compliant indoors

http://www.southwire.com/ProductCatalog/XTEInterfaceServlet?contentKey=prodcatsheet371

 

[GoldDigger]

This is the page from Sothwire so I am not sure what type of insulation it has. It may not be compliant indoors

http://www.southwire.com/ProductCatalog/XTEInterfaceServlet?contentKey=prodcatsheet371

I see this:

exceeds all grade and type requirements of
ANSI/ICEA S-81-570 and UL Standard 854 for Type USE-2.

But that is not at all the same as actually being UL listed.
And the distinction I would make would not be simply inside versus outside, it would be the combination of that with NEC versus not NEC.
IMHO it can be used outside up to the utility-defined service point, although a particular POCO might not even accept that.
It cannot be used as an NEC-covered feeder or branch circuit even if it is entirely outside, nor can it be used for that potion of a run to the service point which passes inside the building. (The latter is my interpretation of what is reasonable, not based on a particular code cite, since the whole issue of NEC scope for service conductors is controversial.)

Now if it is actually NRTL listed as USE-2, then a lot more uses open up.