Oil resistant insulation

[chadkadamson@gmail.com]

I am currently looking for any documentation on the oil resistant insulation value for THHN wire. I am having issues with an inspector constantly writing citations on small amounts of oil coming in contact with double and sometimes tripled protected wires (rub guard, fiber sheathing, and the wire insulation). I have looked through the UL website but can't find anything specifically saying the wire can sustain X amount of time in contact with oil. If any one could help I would appreciate it.

 

[Dennis Alwon]

THHN is not oil resistant. Look at Table 310.104 in the 2011 NEC and table 310.13 in the 2008NEC

 

[Dennis Alwon]

MTW is the only one I see that is oil resistant.

 

[jim dungar]

MTW is the only one I see that is oil resistant.

Southwire does not agree with you.

[FONT=Arial, Helvetica]Southwire Type THHN or THWN-2* conductors are primarily used in conduit and cable trays for services, feeders, and branch circuits in commercial or industrial applications as specified in the 2008 National Electrical Code. When used as Type THHN, or T90 Nylon conductor is suitable for use in dry locations at temperatures not to exceed 90 ?C. When used as Type THWN-2* or TWN75, conductor is suitable for use in wet or dry locations at temperatures not to exceed 90 ?C or not to exceed 75 ?C when exposed to oil or coolant.

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http://www.southwire.com/ProductCatalog/proddetail.jsp?htmlpreview=true&token=1&desc=CU-THHN

 

[Dennis Alwon]

Southwire does not agree with you.


http://www.southwire.com/ProductCatalog/proddetail.jsp?htmlpreview=true&token=1&desc=CU-THHN

Well that is not what the NEC states so I guess the OP has something to go back to the inspector with and make a stink.

 

[jim dungar]

Well that is not what the NEC states so I guess the OP has something to go back to the inspector with and make a stink.

Where do you find the NEC saying what the insulation is rated for?
In 2008, 310.9 made no mention of what type of insulation could be considered as 'oil resistant', this is in marked contrast to 310.8 for wet and dry locations.
310.10(D) requires insulation to be marked with any special characteristics (personally I have yet to see THHN which is not marked oil and gasoline resistant).
Table 310.13(A) has a coumn listed as Trade Name, but that seems to be all but useless for selecting insulation types. This table also has a column for Application Provisions, but there is not a single item listed for the corrosive conditions in 310.9.

 

[Hv&Lv]

I am currently looking for any documentation on the oil resistant insulation value for THHN wire. I am having issues with an inspector constantly writing citations on small amounts of oil coming in contact with double and sometimes tripled protected wires (rub guard, fiber sheathing, and the wire insulation). I have looked through the UL website but can't find anything specifically saying the wire can sustain X amount of time in contact with oil. If any one could help I would appreciate it.

See page 10 (chart) and page 20 (number 45) Save a copy to your documents for future reference...

 

[Dennis Alwon]

Where do you find the NEC saying what the insulation is rated for?
In 2008, 310.9 made no mention of what type of insulation could be considered as 'oil resistant', this is in marked contrast to 310.8 for wet and dry locations.
310.10(D) requires insulation to be marked with any special characteristics (personally I have yet to see THHN which is not marked oil and gasoline resistant).
Table 310.13(A) has a coumn listed as Trade Name, but that seems to be all but useless for selecting insulation types. This table also has a column for Application Provisions, but there is not a single item listed for the corrosive conditions in 310.9.

What about the Tables 310.13 as I mentioned before.

 

[jim dungar]

What about the Tables 310.13 as I mentioned before.

Where in table 310.13 would you find any valuable information? As I said, the 'trade name' column is all but meaningless, and there is not a single oil related item in the application provisions column (even though that is the name of the table).

Using table 310.13, what insulation is rated for exposure to sunlight?

 

[Dennis Alwon]

Where in table 310.13 would you find any valuable information? As I said, the 'trade name' column is all but meaningless, and there is not a single oil related item in the application provisions column (even though that is the name of the table).

Using table 310.13, what insulation is rated for exposure to sunlight?

I see your point.:thumbsup:

 

[chadkadamson@gmail.com]

ok, I am new to this forum. Is this a consensus that everyone believes the THHN to be oil resistant up to 90 Celsius?

 

[don_resqcapt19]

Based on the UL Guide Information for Thermoplastic Insulated Wire (ZLGR) I don't think THHN is listed for contact with oil. It also appears that THWN is, but only if marked "Gasoline and Oil Resistant"

THHN ? Indicates a single conductor having flame-retardant and heat-resistant thermoplastic insulation with a jacket of extruded nylon or equivalent material. The wire is rated 90?C dry only.

THWN ? Indicates a single conductor having flame-retardant, moisture- and heat-resistant thermoplastic insulation with a jacket of extruded nylon or equivalent material. The wire is rated 75?C wet or dry. THWN wire suitable for exposure to mineral oil and to liquid gasoline and gasoline vapors at ordinary ambient temperature is marked "Gasoline and Oil Resistant I" if suitable for exposure to mineral oil at 60?C, or "Gasoline and Oil Resistant II" if the compound is suitable for exposure to mineral oil at 75?C. Gasoline resistant wire has been tested at 23?C when immersed in gasoline. It is considered inherently resistant to gasoline vapors within the limits of the temperature rating.

 

[Hv&Lv]

Based on the UL Guide Information for Thermoplastic Insulated Wire (ZLGR) I don't think THHN is listed for contact with oil. It also appears that THWN is, but only if marked "Gasoline and Oil Resistant"

Looking at the UL white book, I read the section you refered to. Also included in that section are additional markings that can be applied to wires that meet the criteria. Looking at page 11 at the chart, thhn has a (45) under oil resistance. Looking at page 19 at (45), it explains product evaluations criteria.
That being stated, I thought most thhn was dual rated now(thhn/thwn), maybe the supply house stopped carrying straight thhn wire...:huh:

 

[renosteinke]

I can't link to a source right now .... but I seem to recall UL recently addressing the issue of THHN vs. MTW, and stating something to the effect that, for the common sizes, the two are one and the same- at least in stranded form.

Maybe someone else also saw this little item?

 

[jim dungar]

I can't link to a source right now .... but I seem to recall UL recently addressing the issue of THHN vs. MTW, and stating something to the effect that, for the common sizes, the two are one and the same- at least in stranded form.

Maybe someone else also saw this little item?

They maybe interchangeable for application/listing purposes, but they are definitely constructed differently.

 

[Dennis Alwon]

If what UL states about thwn is true then southwires comments are not exactly correct. So the manufacturer says it is good for oil but UL says NO-- so what do you do---

 

[jim dungar]

If what UL states about thwn is true then southwires comments are not exactly correct. So the manufacturer says it is good for oil but UL says NO-- so what do you do---

The Southwire quote I posted, says the same thing as UL. THHN/THWN-2 when used as THWN-2 may be rated for use with oil.
Insulation rated for use with oil must be marked as such, per UL and the NEC.

 

[Dennis Alwon]

The Southwire quote I posted, says the same thing as UL. THHN/THWN-2 when used as THWN-2 may be rated for use with oil.
Insulation rated for use with oil must be marked as such, per UL and the NEC.

This is Don's Quote

Based on the UL Guide Information for Thermoplastic Insulated Wire (ZLGR) I don't think THHN is listed for contact with oil. It also appears that THWN is, but only if marked "Gasoline and Oil Resistant"

I will have to check if all thwn wire is marked that way

 

[Dennis Alwon]

Interesting- I just checked some green thhn that I have and it is dual rated--- thhn or mtw and states gasoline and oil resistance- not sure all of it is marked that way.

 

[tkb]

Southwire does not agree with you.


http://www.southwire.com/ProductCatalog/proddetail.jsp?htmlpreview=true&token=1&desc=CU-THHN

Southwire THHN is also rated THWN and MTW