wire marking

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I guess I should have not disagreed. I should have asked the question.
Bob, thanks for clearing that up for me (310.13). I should have asked the supplier to send MTW 60c. I always just asked for MTW. I would get 90c wire that is not the wire of my choice for panel building. The thermoplastic coating is the difference I assume. I did not know that the wire I wanted was rated at 60c.

dlhoule,
Wire size depends on the control circuit load. When building motor control panels you sometimes have NEMA 5 size contactors. The coil in this contactor or contactors can consume a good bit of current. It just depends on the load.

MTW at 60c is larger in diameter (insulation) than MTW 90c. The thermoplastic coating on the 90c wire is much more slick than the 60c wire. That is why I would not want to be pulling it in conduit, and I don't think it is intended for that purpose. But that does not mean you can't. Personal preference.
 
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Just to throw it out there, but the wire was marked exactly as stated in the OP also marked sunlight resistant.
 
K2500 said:
Just to throw it out there, but the wire was marked exactly as stated in the OP also marked sunlight resistant.
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Did you check out the link I provided?

Roger
 
John Valdes said:
I disagree on MTW. I would order MTW for wiring panels and sure enough they would deliver THWN. MTW has a very soft insulation without the thermoplastic outer coating. It is also rated 90c. This type of wire is not intended for pulling in conduit.
It resembles automotive wire in appearance and flexibility.
I have seen some MTW thats looks and feels just like THHN?
I wonder if there are different types of MTW?
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16 and smaller is dual rated MTW/THWN.
If you want real MTW you have to order it. I am now using TEW - I think thats what it is, the spools are at my shop.
 
roger said:
Did you check out the link I provided?

Roger
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Roger I looked at the link and I really am not following it.:confused:

That appears to be taking about a dual rated conductor.

If the conductor is dual rated and and one of the ratings is not MTW then I agree it could be used in many applications.

However if the conductor is rated only as MTW in my opinion Table 310.13 severely limits its application.
 
Bob, in the OP it was asked if a conductor is marked "MTW or THHN or THWN-2", this is what the link was for.

Iwire said:
If the conductor is dual rated and and one of the ratings is not MTW then I agree it could be used in many applications.
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The THHN in the link is also rated MTW and THWN-2 and Sunlight resistant.





600 Volts. Copper Conductor. Thermoplastic Insulation/SIM Nylon Sheath .​


Heat, Moisture, Gasoline, and Oil Resistant 1 Rated MTW and THWN-2
Sizes through 500 kcmil Listed T90 Nylon or TWN 75. NOM-ANCE 90(D)C.



Size 1/0 and Larger Listed for CT Use. Black Sizes Listed Sunlight Resistant.


Sizes through 500 kcmil Listed FT1. SIM Technology? for easier pulling.

​


​
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Roger​


 
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I guess I overlooked the OP.:D

It seems kind of obvious to me that a conductor marked "MTW or THHN or THWN-2" is in fact all of those conductors.

I was focused on Johns post about conductors simply marked MTW.

If I order MTW I would not be happy with a conductor that behaves like THWN-2.
 
Tom,
If I remember correctly you are absolutely correct. TEW is what I should have been ordering all along. And I believe that is what the supplier exchanged for the thermoplastic coated MTW they sent me originally.
 
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