XHHW ALU Wire

[maghazadeh]

Hello everyone,
I don't have access to NEC book and my question is, if type XHHW alum wire is rated for 90 degree and if heat resistant. I am planning to use it to wire transformer.

 

[charlie b]

Type XHHW is listed in the 90C column of Table 310.16, so I infer it is rated for 90C. I don't know what you mean by "heat resistant."

Welcome to the forum.

 

[maghazadeh]

in chapter 310 as an example lists type THW heat resistant, but does not list XHHW as such, bottom line, is it okay to use XHHW in a transformer subject to heat for pri & sec wiring? in the past I only used THHN for same application.

 

[C3PO]

The two "HH" in XHHW mean that it is rated for 90C per the UL White Book.

 

[billsnuff]

from uglys 2005

from uglys 2005

Thermost - moisture resistant

90d dry and damp locations

75d wet locations

xhhw-2 90d for dry and wet locations

 

[maghazadeh]

So do you guys think it is okay to use that to wire pri & sec of a dry type transformer? transfomer is a 225 KVA 480V-to-120/208V 3phase.
I only used THW or THHN for Xmer in hte past.
Thnks for the input.

 

[jamesoftn]

The termination temperature rating per 110.14 needs to be considered also.