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MaMa Mount
12-26-2008, 01:00 PM
Is is ok to place a plug on the end of a NM electrical cable and use it as pictured below. This set up was powering a power ventilator at the roof. It justs looks inappropriate to me.

Hope everyone had a Merry Christmas. Lets all hope that 2009 is a better year for sure.

Jerry Peck
12-26-2008, 06:35 PM
Is is ok to place a plug on the end of a NM electrical cable and use it as pictured below. This set up was powering a power ventilator at the roof. It justs looks inappropriate to me.

That's because *IT IS* "inappropriate".

You got that one right on the mark.

Roland Miller
12-26-2008, 08:40 PM
Besides being inappropriate, The National Electrical Code is clear that NM cable is not a code compliant cable for an attachment plug. Article 400.

Jerry Peck
12-26-2008, 08:46 PM
Besides being inappropriate, The National Electrical Code is clear that NM cable is not a code compliant cable for an attachment plug. Article 400..

"The National Electrical Code is clear that NM cable is not a code compliant cable for an attachment plug."

That is what makes it "inappropriate" ... the NEC.

Not just Article 400, but, first and foremost, 110.3(B). :)

Rick Hurst
12-26-2008, 11:16 PM
Can't tell you how many disposers I see wired just as that picture.

Rick

Jerry Peck
12-27-2008, 08:11 AM
Can't tell you how many disposers I see wired just as that picture.

Rick.

And you've always written them up, and you will continue to do so.








Right? ;)

Roland Miller
12-27-2008, 09:20 AM
Since the AHJ can accept alternate methods and materials, this simply becomes an issue that does not comply with the NEC. I also have installed an attachment plug in this manner for years, because it was an accepted practice. U.L. lists an attachment plug just for termination directly to branch circuit conductors. It is just extremely difficult to discern these for those that are required to be terminated on Article 400 cords and cables. To say this is not appropriate is, to say the least, a "non-statement."

Jerry Peck
12-27-2008, 12:55 PM
Since the AHJ can accept alternate methods and materials, this simply becomes an issue that does not comply with the NEC..

Roland,

The AHJ cannot just willy-nilly accept non-code compliant items as it wants. That section does not allow the AHJ to disregard the code, that section simply "allows" the AHJ to accept and approve the installation on equipment and materials not addressed in the code.

Only by special permission is the AHJ allowed to "waive specific requirements in this Code or permit alternative methods where it is assured that equivalent objectives can be achieved by establishing and maintaining effective safety."

An "special permission" means *IN WRITING*:

From the definitions.
Special Permission. The written consent of the authority having jurisdiction.

Roland Miller
12-27-2008, 02:15 PM
"By special permission, the authority having jurisdiction may waive specific requirements in this code or permit alternative methods where it is assured that equivalent objectives can be achieved by establishing and maintaining effective safety."

You see, Jerry, what you stated is not quite the whole truth as it is applied by Article 90. Most AHJ's will stick with a close interpretation of the NEC but some that know what they are doing often give exception to some things. The attachment plug on NM cable is just one example of something that really has nothing to do with violating electrical safety and is often allowed. I have seen this on a multitude of jobs and not witnessed one indication that the installation was not safe. And good luck getting anything in writing from an AHJ. About as close as you will get is a green tag for the installation.

Jerry Peck
12-27-2008, 06:27 PM
.Only by special permission is the AHJ allowed to "waive specific requirements in this Code or permit alternative methods where it is assured that equivalent objectives can be achieved by establishing and maintaining effective safety."

An "special permission" means *IN WRITING*:

From the definitions.
Special Permission. The written consent of the authority having jurisdiction.


You see, Jerry, what you stated is not quite the whole truth as it is applied by Article 90.

Roland,

*It is* "the whole truth".

Do all AHJ follow it? I don't know, *BUT THEY SHOULD*.

No AHJ that I have every worked in or know about will accept that use for a cord cap on NM cable.

No green tag anywhere I've ever been.

Then again, it must be remembered that *not all areas even use any building codes, much less the NEC.

One recent IAEI News listed the different codes which are in effect in *major* areas across this country, it did not delve into all small areas, and some of those are still using ... (believe it or not) ... the 1984 NEC ...

Granted, that is better than having no electrical code, but not much better.

I also find it quite strange that you go to the UL White Book and deem using a GFCI as a code violation of 110.3(B), then flip-flop to trying to justify using these and trying to call it not a violation of 110.3(B).

Strange, very strange indeed.

Roland Miller
12-27-2008, 07:16 PM
I called it as a code violation. But have seen it many times. I also know that AHJs can take a great deal of liberty with the article quoted. Some local jurisdictions even write their own rules. You are lucky not to get 150 pages of "this is how we do it here" with your permit.
Do I personally view it as an "electrical safety" issue--No..

In fact there are only a few chapters in the NEC that actually address electrical safety. The rest are just installation instructions for various special interest groups.

I think U.L. is a good guideline. If they hadn't gotten so full of themselves over the years they would be in a much better position. U.L. tests products according the the manufacturers written instructions, plus a few basic electrical safety tests. That is why the AHJ is given the authority to accept issues on their own. The manufacturer couldn't possibly think of or cover everything for everyone. Most of heavy manufacturing wouldn't even exist if AHJs didn't have the authority to accept installations that weren't "picture perfect".

Rarely, as an AHJ, did I find a textbook perfect installation and had to pass judgement on an installation that was close. My job was to make sure it was electrically safe. That's where most all textbook jockey inspectors fail to meet the mark....

Rick Hurst
12-27-2008, 07:28 PM
.

And you've always written them up, and you will continue to do so.








Right? ;)


Yes Sir, I have always written them up. :cool:

Roland Miller
12-27-2008, 07:42 PM
Really out of all this bantering it only comes down to one thing--- just write it up.... unless you are the AHJ, it is not your job to make sure it is fixed. Or is it???:confused:

Jeff Remas
12-28-2008, 12:44 AM
Rarely, as an AHJ, did I find a textbook perfect installation and had to pass judgement on an installation that was close. My job was to make sure it was electrically safe. That's where most all textbook jockey inspectors fail to meet the mark....

I agree to a point. When I do code inspections I can fail just about every single one of them if I wanted to be a prick. You simply cannot find perfection in the construction industry so you have to pick and choose your battles. Is the installation safe and did it meet the intent of the code? This is what you need to be asking yourself.

Electricians can be hammered on the code on a daily basis for simple violations like NM cable bending radius, secured within the specified distance to boxes, enclosures, etc. Of course depending on the attitude, behavior and overall job quality, those items may just be cited but not always.

Here is a photo of a very professional electrical installation that has at least 3 code violations visible:

http://remasinspections.com/images/ProPanel.JPG

Jerry Peck
12-28-2008, 06:54 PM
Jeff,

It is best if you put the photos in as a link instead of internally within your posts for several reasons, here are two of them:

1) Not everyone has a broadband connection and the photos take time to load, including the photos within the posts does not give the viewer the option to read the post without having to wait for the photo to load.

2) When the photo is linked below the post, the photo opens to a second window, the photo and posts can be looked at together, side-by-side if one likes. Makes it easier to read the post and look at the photo, no scrolling up and down.

Jerry Peck
12-28-2008, 06:59 PM
Here is a photo of a very professional electrical installation that has at least 3 code violations visible:.

I see at least four code violations (one is correctable simply by doing some math ;) ).

What are the three which you see?

Michael Thomas
12-28-2008, 07:25 PM
The explanation I have read for prohibiting NM in plug connected applications is that such applications are a subset of the general rule that solid conductor wiring is undesirable in any application where it is subject to repeated bending or vibration.

Michael Greenwalt
12-29-2008, 11:04 AM
Trying to determine if something meets the "intent" isn't part of my job; never has been, never will be. I don't work for the manufacturer or their engineering dept or even the ICC authors. I could never assume that I have the knowledge or experience to effectively determine "intent" over the experience of those listed above; whom I might add state "in writing" what the correct method is.
Assuming that the experts have established the correct method I feel it is pretty safe to inform my client when it does not meet those standards. The client can determine intent if they desire.
I won't give the electrician a by just because their work looks nice. If they didn't do it right, and I can identify, note, and inform...I do. The electrician can justify his/her position to the client easy enough.
I prefer to take care of the client over the tradesman or the agent. (not that anyone else doesn't) and that ideology has me sleeping well at night.

John Steinke
02-03-2009, 08:29 PM
There are various strain relief tests performed by listing agencies on things like plugs .... they hang a weight from the cable for a period, and see if the cable pulls out.

I've attempted these tests with various things attached to romex, and they invariably fail to hold the weight for the required time.

Therefore, I am comfortable in saying that the plug is not approved for use on romex, as it fails to provide the necessary strain relief.

MaMa Mount
03-12-2009, 02:07 PM
Is this itty bitty amount of paint in the panel a problem and what about the wiring with the paper stickingout of it. Looks like it could be a fire hazard.

Hope all is well. I been slower than a postman delivering an assistance check.

Jerry Peck
03-12-2009, 07:32 PM
Is this itty bitty amount of paint in the panel a problem and what about the wiring with the paper stickingout of it. Looks like it could be a fire hazard.

Hope all is well. I been slower than a postman delivering an assistance check.

Well ... I wouldn't worry about that paint with that 'whatever-to-heck-it-is' in that hole where the SE cable comes in/goes out.

I'd probably write it up as something like this: Install proper cable clamp/conduit/fitting as needed to replace unknown and improper material at entry of service entrance cable, and while working on the panel verify that there is no paint on any exposed metallic conductive components/assemblies, such as the bus bars, etc.

That tells the electrician who has that thing torn apart to fix that 'whatever-to-heck-it-is' to check for paint where paint should not be (which includes on those conductors).

I would then add my usual finish statement of 'make sure to correct any and all items which are incorrect and non-code compliant found, including those created during the repair work', that way, when they come away and 'really screw it up', you are covered when a future inspections finds it, such as the forensic fire inspector ... ;)

Questions:

- Is that "service equipment" with the main disconnect in there?

- Is that SE cable the service entrance conductors, or is it going out to a range or dryer?

- Did you mention that the panel has been replaced and permits should be verified?

brian schmitt
03-13-2009, 09:38 AM
jp,
that is your listed black electricians tape on site fabricated bushing when in a pinch for a listed clamp. see it all the time:D

Jerry Peck
03-13-2009, 09:43 AM
jp,
that is your listed black electricians tape on site fabricated bushing when in a pinch for a listed clamp. see it all the time:D

Brian,

I'm not talking about the listed black electrical tape, I'm talking about the listed cardboard/paper sleeve the listed tape is holding in place. :D

Oh, wait, maybe that whatever-it-is is not listed? Oh-my! :)

Rick Hurst
03-13-2009, 10:12 AM
Jerry,

Bet that is a toilet paper sleeve. Just about the right size don't you think?
Recycling at its finest.

rick