ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Increasing demand factors in residential
by gfretwell - 03/28/24 12:43 AM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
0 members (), 260 guests, and 20 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
Joined: Aug 2001
Posts: 545
A
aldav53 Offline OP
Member
They are gradually converting over to 4 prong plugs for electric ranges and dryers. Not much good on the older 2 wire with ground circuits. Is the the new code requiring all 3 wire with ground circuits be run?


The Golden Rule - "The man with the gold makes the rule"
Joined: Feb 2002
Posts: 840
C
Member
What code edition are you using in AZ? The change to 4 wire was first required in the 1996 NEC, so this isn't exactly new.

To answer your question, from the 1996 NEC on requires 4 wire circuits in all new installations. Old 3 wire circuits are permitted to remain.

A feed to a dryer or range that is 2-wire with a bare ground has always been a code violation, and should be replaced no matter what.

Peter

[This message has been edited by CTwireman (edited 08-31-2004).]


Peter
Joined: Oct 2000
Posts: 4,116
Likes: 4
Member
Al,

Yes, all new Electric Range and Dryer circuits installed must be 4 wire. This does not mean that older 3 wire (that were code-compliant) circuits must be replaced.

Bill


Bill
Joined: Oct 2000
Posts: 4,116
Likes: 4
Member
Peter,

sorry, I didn't see your reply.

[Linked Image]
Bill


Bill
Joined: Aug 2001
Posts: 545
A
aldav53 Offline OP
Member
Peter, if older 2 wire circuits were a code violation, then how would they be wired to an older 3 prong plug with 2 hots and a center ground? Which is what was used everywhere.
The center conductor (ground) was used as a current carring neutral for any 120 volt on the dryer.


The Golden Rule - "The man with the gold makes the rule"
Joined: Apr 2002
Posts: 558
C
Member
Older 3-wire range (10-50) and dryer (10-30) receptacles have 2 hots and a neutral but no equipment ground. The neutral was used to ground the non current carrying metal parts of the appliance. As Peter said it has never been code compliant to use an equipment ground as the neutral.

Curt


Curt Swartz
Joined: May 2003
Posts: 2,876
E
e57 Offline
Member
Anyone ever notice that new ranges and dryers are sold without a cord... And instructions for installing both a 3 and a 4 wire cord?

A few times "Appliance Installers" have shown up with only 3-wire cords. (Look at me funny as I explain it too them.)And try to get me to change the receptical to fit thier 3-wire cord.


Mark Heller
"Well - I oughta....." -Jackie Gleason
Joined: Aug 2003
Posts: 173
S
Member
if older 2 wire circuits were a code violation, then how would they be wired to an older 3 prong plug with 2 hots and a center ground?
It was done because people who didn't know what they were doing wired them. Unfortunately this does happen.

Which is what was used everywhere
Just because it was done everywhere doesn't mean it was ever legal.

The center conductor (ground) was used as a current carring neutral for any 120 volt on the dryer.
Again, never was code and is one of the more dangerous mistakes made. Especially with a large metal box usually associated with water.


Speedy Petey

"Anyone who has never made a mistake has never tried anything new." -Albert Einstein
Joined: Sep 2003
Posts: 650
W
Member
I believe that there a bit of confusion.

For large 240V appliances (ranges and dryers), old code permitted the use of the use of the same conductor for both grounding the frame and neutral return of 120V loads. This is _not_ necessarily a violation.

I don't know the details of older code, but in the 2002 code, there are specific descriptions of when such a circuit make be continued to be used. In particular, the ground/neutral wire must either be insulated, or the cable must be service entrance cable. Type NM with two insulated conductors and a bare ground would be explicitly prohibited. But if the install was done using Type MC cable with an insulated ground, then my read says that it can still be used.

All _new_ installs must correctly separate ground and neutral.

I don't see how it could ever be appropriate to connect a three conductor cable to a 4 slot receptacle. Ground and neutral would be shared, but this would be hidden back in the wall.

-Jon

Joined: Nov 2003
Posts: 269
E
Member
Anybody want to speculate how many dryers are out there supplied with 10-2 romex? I have seen a few.


John
Page 1 of 2 1 2

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5