What your failing to recognize is they are approving installations that do no
protect "listed" equipment (tenant owned, property owned, etc.). What's the
purpose of NEC if it isn't to protect the public? What's the purpose of the
listing effort (Testing for Public Safety) if the application of listed
equipment in facilities allegedly complying to NEC do not protect the public
If you have an appreciation for "real" power, you could acknowledge I-squared x
resistance .... that's what a power cord would see. Protected by a 20-ampere
circuit breaker could allow for up to 78% more exposure to power than what the
power cord is rated for if it has a NEMA 5-15 plug and/or cord set. A 20-ampere
circuit breaker does not limit the exposure of the 15-ampere rated device to
15-amperes! A 15-ampere circuit breaker does.
You can overload an extension cord utilizing a NEMA 5-15 plug if protected by a
circuit breaker rated at 20-amperes. However, you cannot overload such
extension cord if protected by a 15-ampere circuit breaker. Acknowledge?
I find it amazing this concept is so difficult to understand by the masses. I
encourage you to contact any listing agency regarding my claims. I cannot
imagine how anyone can misinterpret NEC in such a way that justifies listed
devices not being protected. The words are quite clear in NEC Articles 100,
200, 300, and 400. I've responded to many post on this forum ... and have yet
to be presented an argument that justifies not protecting Listed equipment. In
fact, one response stated "All bets are off" once the installation has been
approved by the regulatory agency ... and "We can't control what the user will
interface with the receptacles" ... which is just not true if NEC is followed as
written (REF: Article 110.3(A)(8) which states: "Other factors that contribute
to the practical safeguarding of persons using or likely to come in contact with
the equipment". The key words are "contribute", "practical", "safeguarding"
.... ACKNOWLEDGED? It just isn't happening if 20-ampere circuit breakers used
in branch circuits are interfaced with "Listed equipment" rated for use from
branch circuit rated at not more than 15-amperes.
I've said enough in the forum to realize the concepts in the NEC are way above
your head, and you just don't have what it takes to understand how it's suppose
to work. Your logic is extensively flawed, and you've not presented anything
resembling a logical argument except for what's referred to as "Appeal to
Authority". If you are an authority, then present a logical argument.
On Fri, 20 Dec 2013 18:44:01 +0000, Let's get it right!
You can easily overload a listed 10 amp extension cord with a NEMA
5-15 plug even on a 15 amp breaker - You seem to be a very strong
advocate for "nanny state" interference at all levels of life - the
government has to protect everybody because they are too stupid to
protect themselves. It's bad enough that way in Canada already. You
can't legislate intelligence, and you can't outlaw stupid. And getting
the government involved in "protecting the people" against everything
just guarantees that "stupid" wins.
Are you a lawyer, or do you just play one on TV?????
This is called an "Appeal to Authority" argument (Goggle it!).
No, I'm not a lawyer. However, I am a Licensed Professional Engineer. I've
engineered "Listed" equipment, and designed branch circuit protection for DOD
facilities. I'm not aware of any fires/shock hazards attributed to my works
over the past 45-years.. However, I've determined the cause of fires of several
facilities .... all due to improper branch circuit protection, and yet the
"As-Built" drawing, reviewed and certified by the local regulatory agency as
complying with NEC, didn't comply!
If there we're accountability for improper branch circuit protection, and the
resulting fires and shock hazards, this problem would be cleaned up. The forum
has really exposed the ignorance and arrogance of the user's of NEC ... and at
I'm prepared to support my argument in court, as I've done in the past! Would
On Mon, 23 Dec 2013 19:46:02 +0000, Let's get it right!
A good friend of mine is working on an "intelligent " power plug
system that would read the power rating of the load and program the
protection level of the outlet to match - but it cannot support an
On 12/23/2013 11:20 PM, firstname.lastname@example.org wrote:
I'm sure you know that a lot of gear has a fused IEC14 inlet on the back
of the case. If the equipment short circuits, the fuse blows and
I would guess prevent an over current on an undamaged power cord. ^_^
On 12/24/2013 10:54 AM, email@example.com wrote:
I seem to recall reading something about New York City not allowing any
power strips whatsoever. Those ubiquitous surge arrester strips were not
to be used by anyone and I found it quite puzzling. If it's true and I'm
not just remembering things that aren't there, perhaps one of my Damn
Yankee cousins could set me straight. ^_^
On Tue, 24 Dec 2013 14:34:59 -0600, The Daring Dufas
When I was working for IBM, the normal commercial power strips were
forbidden. They had some "listed" ones that were used sparingly. The
strips mounted on benches were allowed, but pretty well controlled.
Extension cords were strictly forbidden for anything other than a
*temporary* installation. At my CPoE, I am allotted *one* duplex
outlet. That has to do for not only my four computers (laptops),
three monitors, and all of my lab equipment (scope, power supplies,
meters, etc.). I have power strips plugged into power strips, three
deep. Everyone is in the same situation and some have even more
equipment in their cubes.
On 12/24/2013 4:16 PM, firstname.lastname@example.org wrote:
When I worked as a bench tech at a repair depot, guys were bad about
pranking each other. Our benches had a master switch which controlled
the power outlets on the bench. One hapless victim came in, sat down,
flipped the master switch and it was as though the sun suddenly appeared
for one second because some prankster had wired a bunch of 12 volt dial
lights across the 120 volt supply. I was always switching the contents
of freeze spray and tuner wash in the cans. I'd get an empty can for
each then using my handheld vacuum pump, pull as much of a vacuum as I
could on the empty can after which I simply plugged the small extension
tube between the spay nozzles and depressed them. Freeze spray into the
tuner wash can and tuner wash into the freeze spray can. When the victim
tried to spot cool a component, he got tuner wash all over his work. Of
course it evaporated in a few minutes. I wasn't so mean as to put water
in a can unless I was making a super squirt gun. ^_^
On Tue, 24 Dec 2013 17:44:05 -0600, The Daring Dufas
Forty years ago, we used to prank on each other at work, all the time.
One of my coworkers was a particular target. One time I took the
insulation off some coax (matching all the coax between instruments)
and ran it across the bench in back of his, under the setup he was
testing. When he put a cover on it to do temperature sensing, I blew
smoke through the tube.
One of the other guys filled the tech's pipe tobacco pouch with pencil
shavings and chopped up rubber bands. What was really funny is that
he didn't notice, though everyone else was running for the doors.
On 12/26/2013 10:02 AM, email@example.com wrote:
I only prank those I like and and my pranks are never destructive of
property, unless I supplied the item to be destroyed. I don't prank
those people I don't like because I'm afraid I might become malicious
and I don't like to hurt people, even nasty people. I believe in Karma
and what goes around comes around. I've seen so many ambulatory turds
eventually get their butts nailed to the wall and it's well deserved. ^_^
On Friday, December 20, 2013 1:44:01 PM UTC-5, Let's get it right! wrote:
It's quite obvious that the NEC doesn't agree with your fire and
shock hazard argument. If this were a real problem of any significance,
then the NEC would simply not allow 15 amp receptacles on a 20 amp
circuit. Everyone knows that 95% of people are going to plug any
appliance with a matching plug into a 15 amp receptacle. Very few
are going to go find the panel and figure out whether it has a 15
or 20 amp breaker. And they wouldn't look because not one appliance
manual I've ever bought has said that it had to be used only on a
15 amp circuit. So, why wouldn't the average person just plug it
in? And the NEC, UL, electrical inspectors all know this is going
on in hundreds of millions of homes. Obviously they don't agree that it's a
code violation, illegal, dangerous or why wouldn't they do something
So, if this were indeed a real problem, the
NEC would simply ban putting 15 amp receptacles on a 20 amp circuit.
The fact that they allow it, the fact that electrical inspectors pass these installs every day, says you'be full of baloney.
Why don't you show us some appliance manuals that say the appliance
can only be used on a circuit with a 15 amp rating? Or some fire,
shocks attributed specifically to this. With millions of appliances
and millions of 15 amp outlets on 20 amp circuits that should be
easy to do......
Yes, after all you only have EE's and electricians telling your you're
wrong. We haven't heard from gfre who is/was an electrical inspector,
but I bet he won't agree with you.
And again, if this is indeed a serious safety issue, why the hell does
the NEC allow putting 15 amp receptacles on 20 amp circuits at all?
Everyone knows that people plug all kinds of things into them and almost
no one is going to go look at the breaker. Not that they would even
know to look, because
I'm still waiting for some appliance manuals that say that the appliance
may only be plugged into and used on a 15 amp circuit.
Your logic is extensively flawed, and you've not
They would both be protected with a 15-ampere circuit breaker. The listing you
quote is the steady state current ratings of the device. There is a reserve ...
and at that reserve current (15-amperes), the reliability of the conductors
deteriorates ... but not to the point it would ignite cheesecloth (Ref: U.L.
Standards for listed extension cords and power cords".
You acknowledge a 15-ampere circuit breaker provides more protection than a
20-ampere circuit breaker?
The GFRE with the City of New Orleans certainly does't agree with me ... and
after I proved him wrong. What an arrogant SOB ... and he lacking BACKBONE!
Have a great X-mas season!
We had a bit of disagreement here when I stated that I installed
breakers sized to protect the wiring not necessarily the equipment.
The argument was that according to the NEC, you can use #12 to an
AC unit and a 30 amp breaker. In my experience I've seen burnt
connections and melted insulation when the wiring is installed in that
way. I've measured actual LRA on an AC unit when it was 102°F outdoors
and the current far exceeded what was on the nameplate. ^_^
Happy Horror Days!
On 12/20/2013 12:44 PM, Let's get it right! wrote:
Write a code change proposal. I am confident you will receive the
Petition UL to change its standards. I am confident you will receive the
A 15A circuit breaker does not protect #16 or #18 wires. Include in your
petition to UL and the NEC prohibiting anything smaller than #14 wire.
My desk lamp deserves a #14 cord.
And include in your code change proposal correction for the blatant
over-sizing of protection for fixture wires in 240.5-B-2.
Also include in your code change proposal correction for the blatant
over-sizing of circuit breakers for motors, and even worse, welders. And
I don't even want to think about what they do with fire pumps - it could
cause a fire.
Everyone understands your argument.
As I have explained several times, including quoted above, 110.3
(inspection) is not used for "listed" equipment. The AHJ does not second
guess the listing standard. The AHJ determines the device is used
according to the manufacturers instructions and conditions of listing.
I am a licensed master electrician. I have explained how the NEC and UL
Are you Pete C. in drag?
U.L. isn't the problem. They are doing it right!
The problem is interpretation of NEC. You can't protect a listed device that
utilizes a NEMA 5-15 power cord set from a 20 ampere circuit breaker. Goggle
McMaster Carr, extension cords. None are rated at more than 15-amperes @ 125
VAC. See the problem?
Funny on store bought cords and equipment, the plugs fail either due to bad
crimps, or the little wires breaking off a bit at a time. It usually starts
to get hot right at the end of the molded connector. The more the cord is
moved around, the worse it gets over time.
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