XHHW-2

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bphgravity

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Florida
If the product is listed to ANSI/UL 44, it will be marked as with "gasoline and oil resistant" followed by a "I" or "II", or possibly just GR1 or GR2. The product can also be just oil resistant or just gasoline resistant. Again, the product markings will clearly indicate that by name or by letter code.
 

don_resqcapt19

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Illinois
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Take a look at Table 310.104(A). Unless the XHHW-2 is dual listed as MTW, it is not suitable for exposure to oil, per the NEC.
 

MasterTheNEC

CEO and President of Electrical Code Academy, Inc.
Location
McKinney, Texas
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CEO
Take a look at Table 310.104(A). Unless the XHHW-2 is dual listed as MTW, it is not suitable for exposure to oil, per the NEC.
Incorrect actually.

The listing under UL 44 gives an option to be listed for GRI and II and it has nothing to do with being MTW.

http://www.encorewire.com/wp-content/uploads/EncoreWire-XHHW-SSE1.pdf

Here is the UL option for UL 44 conductors (XHHW-2)

5.17 Gasoline and oil resistance (optional)
5.17.1 To be marked GR I or GR II, insulation, or jackets where used, shall comply with the requirements of Clause 5.16.1 or 5.16.2, respectively, and shall retain not less than 65 percent of their original tensile
strength and elongation after 30 d immersion in water saturated with equal volumes of iso-octane and toluene (ASTM Reference Fuel C) maintained at 23 ?1?C, in accordance with the test, Physical properties (ultimate elongation and tensile strength) ? Gasoline resistance, in UL 2556, CSA C22.2 No. 2556, or NMX-J-556-ANCE.

I accordance with UL 2556 is says :


4.2.8.4 Gasoline resistance


The immersion vessel shall have a minimum volume of 100 ml (6 in3 ). The bottom 25 mm (1 in) of the
vessel shall be filled with tap water, and the remainder of the vessel filled with equal volumes of iso-octane
and toluene maintained at 23 ? 1 ?C.


Note: See ASTM D471 (Fuel C) for the iso-octane and toluene blend.


Specimens shall be suspended in the vessel and maintained at the specified temperature and time.
Specimens shall be suspended in the vessel with care taken to minimize contact with the walls of the vessel or other specimens. Fluid shall not be allowed to get inside a tubular specimen of insulation. In the
case of a jacket, both surfaces (inside and out) shall be exposed to the fluid.


Following immersion, the specimens shall be blotted to remove excess fluid, and allowed to rest for 16 to
96 h at ROOM TEMPERATURE .


Ultimate elongation and tensile strength shall be determined using the apparatus and procedure outlined
in Clauses 4.2.3 ? 4.2.6. Gauge marks shall be applied after the conditioning.

We test ours to UL 2556 so yes it's GR I and II...its on our legend also
 

Dennis Alwon

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Chapel Hill, NC
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I would not say that Don was incorrect. If the wire is simply XHHw-2 then it is not oil resistant however if it is dual rated with MTW then it would be oil resistant. Now there is obviously other markings that it can have also but we generally see XHHW-2 dual rated with MTW-- same with THHW-2.
 

don_resqcapt19

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Incorrect actually.

The listing under UL 44 gives an option to be listed for GRI and II and it has nothing to do with being MTW.

http://www.encorewire.com/wp-content/uploads/EncoreWire-XHHW-SSE1.pdf

Here is the UL option for UL 44 conductors (XHHW-2)

5.17 Gasoline and oil resistance (optional)
5.17.1 To be marked GR I or GR II, insulation, or jackets where used, shall comply with the requirements of Clause 5.16.1 or 5.16.2, respectively, and shall retain not less than 65 percent of their original tensile
strength and elongation after 30 d immersion in water saturated with equal volumes of iso-octane and toluene (ASTM Reference Fuel C) maintained at 23 ?1?C, in accordance with the test, Physical properties (ultimate elongation and tensile strength) ? Gasoline resistance, in UL 2556, CSA C22.2 No. 2556, or NMX-J-556-ANCE.

I accordance with UL 2556 is says :


4.2.8.4 Gasoline resistance


The immersion vessel shall have a minimum volume of 100 ml (6 in3 ). The bottom 25 mm (1 in) of the
vessel shall be filled with tap water, and the remainder of the vessel filled with equal volumes of iso-octane
and toluene maintained at 23 ? 1 ?C.


Note: See ASTM D471 (Fuel C) for the iso-octane and toluene blend.


Specimens shall be suspended in the vessel and maintained at the specified temperature and time.
Specimens shall be suspended in the vessel with care taken to minimize contact with the walls of the vessel or other specimens. Fluid shall not be allowed to get inside a tubular specimen of insulation. In the
case of a jacket, both surfaces (inside and out) shall be exposed to the fluid.


Following immersion, the specimens shall be blotted to remove excess fluid, and allowed to rest for 16 to
96 h at ROOM TEMPERATURE .


Ultimate elongation and tensile strength shall be determined using the apparatus and procedure outlined
in Clauses 4.2.3 ? 4.2.6. Gauge marks shall be applied after the conditioning.

We test ours to UL 2556 so yes it's GR I and II...its on our legend also
I don't see GR-I or GR-II as being a type of insulation permitted by the NEC.

How does a UL standard change a code rule? Table 310.104(A) applies to the conductors used under the rules of the NEC, and if the conductor is not shown as suitable for use with gas and oil, in that table, it cannot be used with gas and oil and be in compliance with the NEC.
310.104 Conductor Constructions and Applications
Insulated conductors shall comply with the applicable provisions of Table 310.104(A) through Table 310.104(E).
 

MasterTheNEC

CEO and President of Electrical Code Academy, Inc.
Location
McKinney, Texas
Occupation
CEO
I don't see GR-I or GR-II as being a type of insulation permitted by the NEC.

How does a UL standard change a code rule? Table 310.104(A) applies to the conductors used under the rules of the NEC, and if the conductor is not shown as suitable for use with gas and oil, in that table, it cannot be used with gas and oil and be in compliance with the NEC.
Are you saying that you believe the ONLY wire that can be used in a GR I and II environment is MTW cause the NEC says that in 310.104(A)?

When we make MTW that is a given component that it must meet, to get it for XHHW-2 or even THHN/THWN-2 it is optional in the standard but it will be listed as such per 310.120(D). For example none of the conductors and subsequent insulation in 310.104(A) refer to low smoke....or sunlight resistant for that fact....but if the manufacturer tests for it and marks it in accordance with UL 2556 and the guidelines of the individual standard then it is fine...in fact it exceeds the MTW ratings.

Sorry Don..when I said wrong I was referring actually to the notion that only MTW can be listed for GR I and II
 

MasterTheNEC

CEO and President of Electrical Code Academy, Inc.
Location
McKinney, Texas
Occupation
CEO
However it does hold true for our THHN/THWN-2 as that is also evaluated as MTW also....it just gets different when we move into the thermoset products...do Don as Dennis said I did not want you to think I was saying you were all wrong....as I was kinda more so targeting the XHHW-2...which does pass all the tests for MTW and others under UL 2556 and this we mark on our products ok for GR I and II
 

don_resqcapt19

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Location
Illinois
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Are you saying that you believe the ONLY wire that can be used in a GR I and II environment is MTW cause the NEC says that in 310.104(A)? ...
That is exactly what I am saying. There is nothing in the NEC about the markings of GR I and GR II. The table is a conductor application table and the only marking suitable for use in applications that have the conductor in contact with gasoline or oil is the marking "MTW".
If you want to use XHHW for that application, then it also needs the MTW marking on the conductor.
....as I was kinda more so targeting the XHHW-2...which does pass all the tests for MTW and others under UL 2556 and this we mark on our products ok for GR I and II
But those markings have no meaning under the rules of the NEC.
 

MasterTheNEC

CEO and President of Electrical Code Academy, Inc.
Location
McKinney, Texas
Occupation
CEO
That is exactly what I am saying. There is nothing in the NEC about the markings of GR I and GR II. The table is a conductor application table and the only marking suitable for use in applications that have the conductor in contact with gasoline or oil is the marking "MTW".
If you want to use XHHW for that application, then it also needs the MTW marking on the conductor.

But those markings have no meaning under the rules of the NEC.
You better inform the Wire and Cable Industry....ours along with all the others have XHHW-2 as being GR I and II and are evaluated for it and marked on the conductors insulation as being suitable for GR I and II. All this was vetted through UL.
 

MasterTheNEC

CEO and President of Electrical Code Academy, Inc.
Location
McKinney, Texas
Occupation
CEO
Just got off the phone with a individual we work with often at UL and he states that the MTW is a stand alone product that already has evaluations for use in Oil and Gas while it is an option under UL 44 and 83. He also stated that the XHHW-2 that is evaluated for the exposure has meet the requirements but does not need to have MTW on the legend if it has GRI or GRII on it. So at this point we ( along with all the other manufacturers) will continue to list it as such as I have never seen an issue before. The manufactures have labeled it accordingly.

We will just let the 90.4's of the world continue to accept as well as the 110.3(B) also I guess:angel:
 

don_resqcapt19

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Location
Illinois
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retired electrician
You better inform the Wire and Cable Industry....ours along with all the others have XHHW-2 as being GR I and II and are evaluated for it and marked on the conductors insulation as being suitable for GR I and II. All this was vetted through UL.
UL doesn't write the code and can't change code rules without submitting public inputs.

This looks like UL and the NEC are out of step on this one. UL or the cable industry needs to submit a public input on this issue.
There is no provision of the NEC that permits a conductor without the MTW marking to be used in an application that involves exposure to gasoline and oil. It really doesn't matter what UL or the manufacturers tell us...the code rule is clear.

Sure a reasonable inspector would accept the XHHW based on the information that you have provided but there is no reason for this disconnect between the product standards and the NEC.
 

MasterTheNEC

CEO and President of Electrical Code Academy, Inc.
Location
McKinney, Texas
Occupation
CEO
UL doesn't write the code and can't change code rules without submitting public inputs.

This looks like UL and the NEC are out of step on this one. UL or the cable industry needs to submit a public input on this issue.
There is no provision of the NEC that permits a conductor without the MTW marking to be used in an application that involves exposure to gasoline and oil. It really doesn't matter what UL or the manufacturers tell us...the code rule is clear.

Sure a reasonable inspector would accept the XHHW based on the information that you have provided but there is no reason for this disconnect between the product standards and the NEC.

I do believe (AGREE) it should have the UL 1063 rating marked on it (MTW) as well but it does not appear which could raise an issue if confronted. However, since UL 1063 is basically a scope for Thermoplsastic and not ThermoSet you are also correct again (batting 1000 now) that it would take a change to the UL 1063 to effectually mark XHHW-2 as MTW.....We know that it exceeds the evaluation value of MTW .....looks like I have another thing to present for a change to the W & C Guys.
 
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MasterTheNEC

CEO and President of Electrical Code Academy, Inc.
Location
McKinney, Texas
Occupation
CEO
I can only echo what I hear in the W&C industry and that is that the base listing is for XHHW-2 and most of us test it and have it evaluated in order to mark it GR I and II. They believe that under this optional testing that it can be marked as such and used in such an environment. It is clearly being accepted as it has not been an issued raised before that I am aware of.....so their are some "reasonable inspectors" out there...lol

We can't just place MTW on XHHW-2 because of the UL 1063 standard only applying to Thermoplastic....but I will ask you this.....in Table 310.104(A)....how many are listed as sunlight resistant....?

None in the table...so would you not allow any of them to be used? or would you permit any of them that are marked as such in accordance with 310.120(D)?
 

MasterTheNEC

CEO and President of Electrical Code Academy, Inc.
Location
McKinney, Texas
Occupation
CEO

MasterTheNEC

CEO and President of Electrical Code Academy, Inc.
Location
McKinney, Texas
Occupation
CEO
Don,

(My Opinion) Here is where I believe your disconnect is coming from. The Table in 310.104(A) is acceptable insulations for use in building wiring. Clearly XHHW-2 is listed and the table gives is basic parameters of design. However, it also gives the basic parameters of design for MTW as well and it inherently has the oil resistant statement, but ironically nothing about Gas.

When a Wire and Cable Manufacturer produces a conductor and insulates it to meet XHHW-2 standards, it is evaluated for many things beyond the NEC. As far as the NEC is concerned (again we can agree to disagree) as long as the W & C manufacturers produce a XHHW-2 and have their compounds tested and listed for such that it clearly can be used in GRI or II applications. Now, keep in mind that not all manufactures produce compounds that are incorporated into the XHHW-2 creation that will meet GRII...some will only meet GRI but we have a chemical lab and a 13 million dollar R & D department and have met the ability to mark GRII on our XHHW-2. (Others may as well)

So while MTW is clearly shown for oil-resistant...it is not (we do not see the chart the same way you see it) the only option. So I do not believe their is a disconnect between UL and the NEC. However, I do respect your opinion and it is duly noted my friend.
 

don_resqcapt19

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Location
Illinois
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Don,
...
So while MTW is clearly shown for oil-resistant...it is not (we do not see the chart the same way you see it) the only option. So I do not believe their is a disconnect between UL and the NEC. However, I do respect your opinion and it is duly noted my friend.
That is where we differ. I see the table as an absolute as far as the application of the conductors are concerned and the only type that is shown as gas and oli resistant is MTW. There is no provison to use any conductor without that marking in an application that involves gas and oil contact per the NEC.
 
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