Motor Lead Wire 2

[flandrax]

I was wondering if there was a limitation to how long leads could be on a motor?
Can they be run in conduit?
Are there any standards for this?

Thanks in advance,

 

[dpc]

I've never seen motor leads extended beyond the motor terminal box. If the motor lead wire insulation meets NEC requirements AND it is sized per the NEC for motor wiring (which I would doubt), it might be legal.

David Castor

http://www.cvoes.com

 

[electricpete]

NEC requirements includes UL listing for the purpose, correct?

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[electricpete]

Some more info on the AWM designation

http://www.ulenvironment.com/global.../newsletters/electricalconnections/july08.pdf

Internal wiring of equipment may employ UL Listed conductors for general wiring, or
alternatively, use UL Recognized Component Appliance Wiring Material (AWM), which
signifies that the wiring has been subjected to limited testing and evaluation and will be further evaluated in the end-product. AWM wire styles are selected by end-product manufacturers based on their specifi c voltage and temperature ratings, mechanical abuse, environmental exposure, flame ratings, etc. AWM has not been evaluated for general wiring applications in accordance with the NEC.

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[dpc]

Yes, it would have to be a listed type in Article 310. But also see Article 430.245 - it addresses a motor TJB that is physically not attached to the motor.

In general, once the conductors leave the motor TJB, they are in NEC land. Inside the motor and TJB, they are exempt from most NEC requirements for wiring. At least that is always how it has been in my experience.


David Castor

http://www.cvoes.com

 

[electricpete]

430.245 looks somewhat relevant. Although the separation distance is limited to 6 feet, and only when conditions are met.

430.245
(B) Separation of Junction Box from Motor. The junction
box required by 430.245(A) shall be permitted to be
separated from the motor by not more than 1.8 m (6 ft),
provided the leads to the motor are stranded conductors
within Type AC cable, interlocked metal tape Type MC
cable where listed and identified in accordance with
250.118(10)(a), or armored cord or are stranded leads enclosed
in liquidtight flexible metal conduit, flexible metal
conduit, intermediate metal conduit, rigid metal conduit, or
electrical metallic tubing not smaller than metric designator
12 (trade size 3?8), the armor or raceway being connected
both to the motor and to the box.
Liquidtight flexible nonmetallic conduit and rigid nonmetallic
conduit shall be permitted to enclose the leads to
the motor, provided the leads are stranded and the required
equipment grounding conductor is connected to both the
motor and to the box.
Where stranded leads are used, protected as specified
above, each strand within the conductor shall be not larger
than 10 AWG and shall comply with other requirements of
this Code for conductors to be used in raceways.

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[rhatcher]

electricpete, I wish that I had the time to research these things like you do although I will also say that if I had extra time I do not know if I would use it for this purpose.

You have correctly identified the wire that we use since it does have the AWM marking and you have also in the process enlightened me on what AWM means. You have also shown that the NEC states that a motor junction box shall not be more than 6ft from the motor.

However, if I read your posts correctly, you have quoted that "AWM has not been evaluated for general wiring applications in accordance with the NEC." I read this to mean that they have not formed an opinion or, more specifically, that they have not endorsed this use nor have they prohibited it.

Finally, I am wondering, if you say this in your 3/6 21:41 post:

I am not in a position to enlighten you about the maze of UL and NEC requirements

and this in your 3/7 21:10 post:

I don't know enough about NEC requirements for cable to figure out what UL numbers are required

and this in your 3/7 18:26 post:

I don't know enough about NEC requirements for cable to figure out what UL numbers are required

 

[electricpete]

I read this to mean that they have not formed an opinion or, more specifically, that they have not endorsed this use nor have they prohibited it.

I think you can say the NEC does not permit it. You can only use products that are UL listed for the purpose that you use them. There would be an NEC compliance problem if you used the AWM lead wire for general wiring purposes.



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[electricpete]

And no, I am no code expert - that is my opinion from looking around the UL website.

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[rhatcher]

finishing 3/8 19:52 post...

...then why are you now offering advice on the NEC and UL?


electricpete...I obviously hit the 'submit post' button while still editing since I have a quoted you twice with different date/time entries that are erroneous (3/7 18:26 is the correct one). However, the quotes are from this thread. I do not mean to be harsh, especially considering that I complimented you so profusely last night on a different thread.

My point is that anyone can do a 'google search' on a topic and provide quotes from that search whether they fully understand the subject or not. If you are not fully proficient in what you are posting, then you are not offering any more information than the people that come here for help can find on their own doing their own 'google searches' if they are interested in that source of information.

If you simply have a lot of time on your hands (which some people like myself don't but you apparently do) and you can perform 'google searches' to offer information that applies to the question at hand, then you should be very careful to note that you are not an 'expert' but are simply offering information that you have found by searching the internet.

 

[rhatcher]

electricpete, I stand corrected. While I was typing my last response you responded with:

And no, I am no code expert

Sorry, but sometimes you come across quite strong with your opinion when it is obviously based on recent internet research and not actual working experience.

At the same time I will say that sometimes your real strengths shine through brilliantly.

 

[electricpete]

Ray – I feel a need to respond to the comments you made about me. My feedback is that it is a misrepresentation of what has gone on in this thread as anyone can see who reads the thread from the beginning. I expressed a reservation about the NEC/UL status of T-lead cable. I suggested the original poster to post in the power forum. I repeatedly made it clear I was not a code expert in terms that I thought would encourage others to chime in. When the thread seemed to be winding down without any post in the power forum or any code guys chiming in, and without any definitive conclusion emerging about the NEC/UL status of T-lead cable (and one could argue it was leaning the opposite way from my opinion), I decided to get advice from a power engineer at work and do a targeted search with his assistance. The result was presented very clearly for what it was in the form: "So from my bit of research using google I am inclined to think UL 3340 / 3374 is a niche cable intended for use as part of appliances, but not specifically intended for field use." (And by the way, you were expecting someone to clarify the meaning of the UL markings when you posted them weren't you?).

Then, you took this one single thread and tried to weave it into an insinuation that the bulk of my participation in eng-tips is involved with googling things that I know nothing about. I can tell you, I am familiar with the postings of electricpete. The vast majority of my initial responses come straight from my head. I generally only go to google when there begins to be a disagreement and I think there is proof of a point I have made, or when there is a point that comes up that I am unsure of and would like more information, or when I have information available to me in a book that I know can be shared by googlebooks.

I agree I spent a lot of time on eng-tips this weekend, probably more than I should have based on other stuff I should attend to. It is fun for me and sometimes I overindulge. But that is really none of your concern.

I would encourage you to contribute from your considerable knowledge working in motor repair, but don't waste your time critiquing the contributions of others.

I looked two sets of removed T-lead souvenirs in my garage (one had insulation swollen due oil, another associated with a failure). Imprinted on the swollen one is is AWM style 3499. If I knew what 3499 meant, I could tell you that style is susceptible to oil problems. The other had no markings related to AWM or other UL or NEC recognizeable markings. The AWM marking is optional as I read recently. I have a few more T-leads at work that I'm going to look at. But from these first few data points, I suspect AWM T-leads are common. I would love to have a decoder list for that 4-digit style number to help me figure out and confirm what materials are used on our various motor leads. Google didn't find it for me. But if anyone can find it by google or otherwise, I'd be appreciative.

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[electricpete]

I did find 3499 is EPDM (susceptible to oil penetration). I'd still like master decoder list for the 4-digit AWM style number.

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[ScottyUK]

E-pete,

It's not a Belden code by any chance? Their type codes are typically four digit and the range is enormous.

Page 2 of this link shows Belden style 3499. And I ain't an expert on Belden codes, before anyone thinks I am. This came via Google.


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If we learn from our mistakes I'm getting a great education!

 

[electricpete]

Thanks Scotty – I appreciate it (even if it came from google). You are right, this particular cable is labeled as a Belden. The 3499 is a 4-digit AWM style number from UL. I checked the UL website there are in fact three manufacturers certified to provide the AWM style 3499 cable. There is also info available at that site (after filling out registration form) about each of the 4-digit style numbers, but not much different than what shows up in the manufacturer’s pages.

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