Dryer - 3 or 4 prong - ECN Electrical Forums

For new installations are you using 4 wire 4 prong plugs, or 3 wire 3 prong?
I've seen dryer recepts with the neutral and ground tied together on a 3 prong plug.

Al,

New installations must be 4 wire.
see 250.142(B)

Bill

We have been doing 4 wire dryer and range plugs since the '99 revision, I believe.

The owner is usually PO'ed because then we also have to install a new tail on the appliance.

FWIW
GJ

I assume this includes range plugs too. Kinda strange that in the years past they were using the ground wire for a current carring conductor for the 120v clocks and timers in these appliances.

aldav53,

The equipment ground conductor has never been permitted to be used as the neutral for range and dryer receptacles. When using a 3-wire receptacle the neutral is used to ground the frame of the range or dryer.

Curt

In my area normal practice was 10/2 RX for dryers 6/2 AL SE for stoves, the bare was connected to the outlet box as ground and to center terminal of the plug.

For myself I am glad for the change to 4W plugs, if for nothing else but consistency.

Yes the 10-2 wire bare were used as grounds but we all know dryers can have 120v timers etc.

Was 10-2 w/gr ever legal for Dryers?

I thought only SE cable or 10/3 Wo/gr were legit. No books on me at the moment though.
Anybody?

Bill

Bill,

I don't believe so. The bare wire in type SE cable is rated for use as a neutral conductor so it was approved for this use. That was the point I was trying to make with my previous post. I have read many comments in forums about why the 4th (neutral) wire is now required to be installed for range and dryer receptacles. A neutral wire has always been required but now a 4th wire (equipment ground) is also required.

[This message has been edited by caselec (edited 05-09-2003).]

hey bill i hate to add more debate here but look under "moible home " they required 4 wires set up for very long time and i know city of Chigargo ( sorry for spelling) have required the same thing too for many years too i belive they enfore it sometime back mid 60 or early 70's i am not sure when it was in effect i belive it was the same time as mobile home use same way but now it is more common to use 4 wire set up and feel more safer to use it yeah i did use 10-2 some time 10-3 for dryer ditto for stove but use 8-2 or 6-2 before now have to use 6-3 for stove useage

merci marc

Marc,

Yes, I agree that 4 wire has been required for a long time in Mobile Home installations.

Do you know of some code reference that said that 10-2 was ever permitted for Dryer installations? Or 8-2, 6-2 NM cables for Stoves?

Bill

Bill I do not know if 10/2 was "legit" only that it never failed inspection.

This would be around 82 to 86 Boston area.

I was a apprentice then and did what I was told.

Another short cut this company was good for, in sub panel applications we would rough in dryers with 10/3 and stoves with 6/3 AL SER this would pass on rough inspection.

Then when I was sent back to do finish he would have me use 3W outlets and cords, inspectors would never catch this.

When I asked why we bothered to run the right cable in the first place the answer was "because if we get caught we will not have to damage the building finish to fix it. [Linked Image]

I work for a professional company now. [Linked Image]

I have not done mobile homes but aren't they set up with a main breaker outside and subpanel inside?

That would necessitate the 4W outlets to be used.

Bob

bob , yes it is set up that way for mobile home have main disconntion at meter socket outside of mobile home useally up to 30 feet away from mobile home and have underground wire buried or run in conducts ( new one are required to run in conduct anyway) and the size of main breaker varies alot from 50 amps to 200 amps but 100 and 200 is more common and they have breakerbox inside can be either 100 or 200 amp main box. our inspecter allow the outside breaker as main ocpd and sized the conduct as need useally #2 alum or #4 copper depend on type (100 A) or 4/0 alum or 2/0 copper for 200 amps and inside main breaker will still the same but older mobilehome parks have older conducters there and we are allowed the max per conducter it is there .

anymore question just drop a line to me i will try my best to answer it

but i cant find the code refernce about allowing 2 wire appiations i know i did disconute that useage way back early 90's excat time i dont rembemer it . also it is very common in early time to use 10/3's with white wire for both nuterul and ground the same time that was my curpit when i move in usa from france it was backward there i will expain other time with that

merci marc