ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals

Topic Options
Rate This Topic
#89538 - 09/27/04 03:09 PM Dryer downsize nuetral
srscott Offline
Member
Registered: 05/11/04
Posts: 15
Loc: Crystal Lake, IL
Could someone please clarify (2002 NEC)the position of code on downsizing nuetral on residential 240 volt dryer? 220.22 oks it for feeders but not branch circuits. 210.19 (A)3 exception 2 oks it for ovens. What am I missing here?
Thanks, Scott
Top
2017 / 2014 NEC & Related Books and Study Guides
#89539 - 09/27/04 03:40 PM Re: Dryer downsize nuetral
cpal Offline
Member
Registered: 05/17/04
Posts: 162
Loc: Cohasset MA
The Code tends to allow for diversity as the connected load increases. Feeders and Service conductors have more items connected than branch circuits. The Exception to section 210.19 (A) (3) does recognize that in the case of household electric ranges the neutral conductor seldom handles more than 25 A (refer to the explanatory print in the handbook)

The dwelling type Electric dryer on the other hand is typically a smaller branch circuit (30A) and the neutral is always current carrying as long as the drum turns (motor). There is significantly less capacity in the circuit to allow derating the grounded circuit conductor. Also;

210.19 Conductors — Minimum Ampacity and Size.
(A) Branch Circuits Not More Than 600 Volts.
(1) General. Branch-circuit conductors shall have an ampacity not less than the maximum load to be served. NEC Ó

Granted the dryer is not a general branch circuit but I believe the general intent of the Code is to not allow derating on branch circuits. Hope this helps.

Charlie
Top
#89540 - 09/27/04 10:43 PM Re: Dryer downsize nuetral
SolarPowered Offline
Member
Registered: 07/05/04
Posts: 625
Loc: Palo Alto, CA, USA
Plus, people tend to plug other things into "dryer" outlets. Table saws and welders are rather popular (and don't draw any current on the neutral, so they're not a problem here), and I'm sure other things get plugged in there, as well.
Top
#89541 - 09/30/04 02:46 AM Re: Dryer downsize nuetral
Big Jim Offline
Member
Registered: 07/18/03
Posts: 394
Loc: Denver, CO USA
Its not a long term load but a lot of tradesmen carry a pigtail with a dryer plug on one end and 2 duplex in a handybox on the other because so much house wiring is not up to their industrial duty saws, sanders, etc.
Top
#89542 - 09/30/04 11:14 AM Re: Dryer downsize nuetral
George Little Offline
Member
Registered: 01/18/04
Posts: 1488
Loc: Michigan USA
Jim- these must be the same guys that we read about in the obits. Or these same "Tradesmen" who are untrained and use no GFCI protection. I'm sorry, I couldn't help myself.
_________________________
George Little
Top
#89543 - 09/30/04 11:31 AM Re: Dryer downsize nuetral
mustangelectric Offline
Member
Registered: 02/08/04
Posts: 494
Loc: Bentonville, AR
hi,
what is the requirement for reducing the neutral on a residential dryer?

you need a 4 conductor NM cable or you need 4 conductors ran in a raceway. are you saying that you want to reduce the wire from a #10 to #12?

What could you gain or service could you provide from that method? I have never heard of anybody worrying about reducing the neut on a dryer...

-regards

mustang


[This message has been edited by mustangelectric (edited 09-30-2004).]
_________________________
Electricity has no respect for ignorance!
Top

Member Spotlight
Member Since: 01/22/05
Posts: 5316
New in the Gallery:
SE cable question
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box


Who's Online
0 registered (), 95 Guests and 10 Spiders online.
Key: Admin, Global Mod, Mod
 
New in the Gallery:
SE cable question
 
Top Posters (30 Days)
Admin 47
HotLine1 43
gfretwell 19
Ruben Rocha 12
Trumpy 9
 
Newest Members
Scotto, Freecrowder, clee512, Jdscott2005, FAIZAN

ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals