XLPE

nizak

Senior Member
Is Type XLPE insulation not recognized by the NEC?

I’m trying to find it for conduit fill and don’t see it in any of the tables.

Thank you.
 
Not if that's all it says. No other markings like XHHW or USE?
That’s what’s listed in the Mfgrs cut sheet. Don’t have the actual wire in front of me.

Trying to determine if I can get 3- 250 MCM and 1 -3/0 conductor in a 2” EMT.

Will be used as a 4’ sleeve , not pulling through a complete run.

Only have 2” knockouts to work with on disconnects.and need to protect where it emerges from the ground.
 
That’s what’s listed in the Mfgrs cut sheet. Don’t have the actual wire in front of me.

Trying to determine if I can get 3- 250 MCM and 1 -3/0 conductor in a 2” EMT.

Will be used as a 4’ sleeve , not pulling through a complete run.

Only have 2” knockouts to work with on disconnects.and need to protect where it emerges from the ground.
You could run the calc with type USE, as that would be the thickest insulation. If it's aluminum, then of course it's probably compact, but it might be compressed stranded also which is going to be a little larger.
 
The cans I have are factory furnished with 2” KO’s.

Not enough physical space to punch to 2 1/2” and get a locknut on it.
 
Could maybe use something like this:


They are meant to be used as expansion couplings and slip over a piece of 2-in, but most I have seen are actually made of 2.5" inch PVC so you could just glue up a 2.5" coupling to it.

Or simply use a reducer just below the cabinet.
 
XLPE is an insulation material, but not a conductor type.

Why use 2.5" if you're going to reduce it to 2" anyway?

2" EMT is fine for your wires with the nipple allowance.
 
NEC does not detail the insulation material but only the name and properties.
These details are in UL-44 Standard for Thermoset-Insulated Wire and Cable
See Table 5.1 for details.
The details for XL and EPCV are explained in UL 1581 Reference Standard for Electrical Wires,Cables, and Flexible Cords
That means NEC recognized at XLPE as insulation material.
 

Attachments

  • XLPE from UL 44 and UL 1581.jpg
    XLPE from UL 44 and UL 1581.jpg
    353.2 KB · Views: 8
All RHH/RHW and XHHW conductor types now all use XLPE insulation. RHH originally stood for "Rubber High Heat", but they stopped using natural "rubber" decades ago, XLPE is considered a "synthetic" rubber substitute.
 
Top