Reduced neutral to dryer

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kwired said:
For those worried about what someone may plug in there down the road - how can you control that even if you ran 10 AWG for all conductors? Then if the breaker doesn't hold how do you prevent them from swapping with a higher setting breaker? You can only design/install for what you have now, you can't "what if" proof everything, an improved idiot will eventually find a way of messing it up.
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#10 will (should) have a -30R. if a 30A ocpd doesnt hold then there is some other problem.

if you run say #10 to 14-50 and use a 14-50P on the dryer (if it fits ok and is not prohibited), and the ckt has 30A ocpd. ok thats fine, all is protected, except now you have an idiot hazard up front, the 14-50 yells out "i am 50 amps able", but the ocpd doesnt say so, and idiot doesnt really know what awg means, so they swap out 30A for a 40 or 50 ocpd. if the dryer ckt was wired using 14-50R and wire to support 50A ocpd but you install 30A ocpd, thats fine, its also idiot proof.

i feel like some are contradicting NEC intent, which is for the most part, is to be idiot proof within reason.
 
480sparky said:
Let's see the listing for that dogbone......
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Looks like it might be a 14-50 to 6-50 adapter - I don't see a problem with that, drop the neutral in the conversion.

If it is a 5-15 adapter then we may have some overcurrent protection issues.
 
kwired said:
Looks like it might be a 14-50 to 6-50 adapter - I don't see a problem with that, drop the neutral in the conversion.

If it is a 5-15 adapter then we may have some overcurrent protection issues.
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that pic was from a search for 240 to 120 adapter, looks like 5-15. takes one pole, N, EGC. overcurrent issue, how so? ocpd should still be there, but the wire in the adapter better be able to handle 50A. no UL as far as i know.
 
FionaZuppa said:
that pic was from a search for 240 to 120 adapter, looks like 5-15. takes one pole, N, EGC. overcurrent issue, how so? ocpd should still be there, but the wire in the adapter better be able to handle 50A. no UL as far as i know.
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It looks too large in comparison the the 14-50 to be a 5-15 is why I think it is a 6-50.
 
FionaZuppa said:
#10 will (should) have a -30R. if a 30A ocpd doesnt hold then there is some other problem.

if you run say #10 to 14-50 and use a 14-50P on the dryer (if it fits ok and is not prohibited), and the ckt has 30A ocpd. ok thats fine, all is protected, except now you have an idiot hazard up front, the 14-50 yells out "i am 50 amps able", but the ocpd doesnt say so, and idiot doesnt really know what awg means, so they swap out 30A for a 40 or 50 ocpd. if the dryer ckt was wired using 14-50R and wire to support 50A ocpd but you install 30A ocpd, thats fine, its also idiot proof.

i feel like some are contradicting NEC intent, which is for the most part, is to be idiot proof within reason.
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I guess you are right - it is in 90.1

(B) Adequacy.


This Code contains provisions that are considered necessary for safety. Compliance therewith and proper maintenance results in an installation that is essentially free from hazard but not necessarily efficient, convenient, or adequate for good service or future expansion of electrical use.


Informational Note: Hazards often occur because of overloading of wiring systems by idiot installer methods or usage not in conformity with this Code. This occurs because initial wiring did not provide for increases in the use of electricity. An initial adequate installation and reasonable provisions for system changes provide for future increases in the use of electricity.
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:)
 
peter d said:
Actual electricians don't think about this stuff. We run a smaller neutral and move on to the next job.
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:roll: When was the last resi job you ran a #12 noodle to a dryer?


peter d said:
What other people do with my installations is of no concern to me whatsoever. Please stop trying to put your theoretical "what ifs" into real world situations, you have no practical experience as an electrician and shouldn't be lecturing us on what should and shouldn't be done.
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To which you would still need to know the code. The questioned was asked by an electrician, and several other electricians plus engineers and code experts are scratching their heads at code verbiage that strictly forbids this. Sometimes you need to view this from a CMP reasoning perspective.
 
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kwired said:
It looks too large in comparison the the 14-50 to be a 5-15 is why I think it is a 6-50.
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nice catch, i went back and checked specs on that site, it is 6-50R. but search more, you can find 240 to 120 5-R adapters.

@post #85 --->:thumbsup:. TY.
btw, 2011 406 also mentions "idiot proof"
 
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iwire said:
I have no idea why you went to the exceptions when I did not mention them.

In my opinion 210.19(A)(4) does not prohibit a reduced neutral to a dryer.

That said I do have to agree that 210.4(D) is an issue.
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IMHO 210.19 (A) (4) seems irrelevant at first glance, hence why I went to the exceptions which mentioned receptacle outlets... all in all I still do believe this part applies to the OP. IMHO :angel:
 
iwire said:
Nothing? :)

If I install a 50 amp receptacle and 50 amp conductors for a welder and protect them at say 100 amps as very likely allowed by article 630 what is to protect people from themselves there?
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The receptacle. A load with a NEMA 14-50 will not pull more than 50amps. A short circuit would still trip the breaker in theory since its no different than a motor application where a 50amp breaker can protect #12.


In the case of the dryer we have a scenario where nothing will protect the neutral from over load be it breaker or cord cap.
 
It's a dryer in a truck shop I don't know if it has a cord and recep. or not but don't see what difference it makes.
 
mbrooke said:
:roll: When was the last resi job you ran a #12 noodle to a dryer?
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If I'm running conduit to a dryer or range, then I always downsize the neutral. But that #12 might overheat from the heavy load on it. :roll::roll:





To which you would still need to know the code. The questioned was asked by an electrician, and several other electricians plus engineers and code experts are scratching their heads at code verbiage that strictly forbids this. Sometimes you need to view this from a CMP reasoning perspective.
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I follow my own code which is the code of common sense. :thumbsup:
 
peter d said:
If I'm running conduit to a dryer or range, then I always downsize the neutral. But that #12 might overheat from the heavy load on it. :roll::roll:
I follow my own code which is the code of common sense. :thumbsup:
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would you do the same if it were a 208/120 3ph ~25A dryer??
 
peter d said:
Yes, of course. How many amps does the dryer neutral carry?
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3ph has other issue(s) that may crop up onto the "N" with modern day equipment, which may tell you "do not downsize". but anyways, carry on.
 
peter d said:
If I'm running conduit to a dryer or range, then I always downsize the neutral. But that #12 might overheat from the heavy load on it. :roll::roll:
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The #12 won't be over heated by any modern clothes dryer or stove that I know of, in fact Id sleep with #14. However, if someone brings home a kiln that noodle could easily see 24 amps and over:


http://www.paragonweb.com/files/wiringdiagrams/A66WD.pdf

I know, that could be a 14-50 plug. :roll: Now look at the cord here, 18 on the parts list:


http://www.paragonweb.com/files/wiringdiagrams/ACF7828.pdf







I follow my own code which is the code of common sense. :thumbsup:
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Which I admire, but make sure it follows sound reasoning in physics. Physics will never fail you, provided you use it correctly.
 
Tacoma Narrows also was built with common sense mentality :eek:hmy:

but who's bringing that kiln to a truckstop to plug it in :lol::lol:
 
FionaZuppa said:
would you do the same if it were a 208/120 3ph ~25A dryer??
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Perhaps it is time to break out some modern resi dryer wiring diagrams :):

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FionaZuppa said:
3ph has other issue(s) that may crop up onto the "N" with modern day equipment, which may tell you "do not downsize". but anyways, carry on.
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True, but not for a dryer where the only L1-L2 load is the heater (and technically timer in certain parts of the cycle via a small resistor).
 
mbrooke said:
Perhaps it is time to break out some modern resi dryer wiring diagrams :):
True, but not for a dryer where the only L1-L2 load is the heater (and technically timer in certain parts of the cycle via a small resistor).
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nah, no need for logical grams. 3ph with modern day controls may present some harmonics issues. its way beyond this forum to dig into, but at least now you know.
 
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