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NEMA 14-50 to Standard 3 prong outlet?

tdiggity

Member
Oct 3, 2012
725
4
Bay Area, CA
Is it possible to step down a NEMA 14-50 outlet to the standard 3 prong outlet? I'm having a port installed in my condo and figured that I would also install a standard outlet just in case I need to do 120v stuff. But, if I can step the 14-50 down then I wouldn't have to get this installed.

Thanks in advance!
-tdiggity

p.s. what's the standard 3 prong outlet called? NEMA xx-xx
 

gregincal

Active Member
Oct 26, 2012
3,763
2,294
Santa Cruz, CA
The standard 3 prong is a NEMA 5-15. There is no adaptor, because the breaker sizes need to match. The point of a NEMA 5-15 is that you have a cord that is intended to support a max of 15 amps, and if something goes wrong and more current is drawn the breaker flips. If you have a 5-15 receptacle with a 50 amp breaker behind it the cord would catch on fire and burn down your condo long before the 50 amp breaker would flip. You need two different plugs wired to two different breakers.
 

tdiggity

Member
Oct 3, 2012
725
4
Bay Area, CA
The standard 3 prong is a NEMA 5-15. There is no adaptor, because the breaker sizes need to match. The point of a NEMA 5-15 is that you have a cord that is intended to support a max of 15 amps, and if something goes wrong and more current is drawn the breaker flips. If you have a 5-15 receptacle with a 50 amp breaker behind it the cord would catch on fire and burn down your condo long before the 50 amp breaker would flip. You need two different plugs wired to two different breakers.

Thanks. I didn't think it was possible, but I thought i'd ask anyway.

I'll just have the electricians wire up both! For all you condo owners, it's something to think about because what if your 12v battery dies.....or you could power a vaccum cleaner :p
 

TXjak

Owner/Investor/Advocate
Jun 1, 2011
350
68
Austin, TX
Is it possible to step down a NEMA 14-50 outlet to the standard 3 prong outlet? I'm having a port installed in my condo and figured that I would also install a standard outlet just in case I need to do 120v stuff. But, if I can step the 14-50 down then I wouldn't have to get this installed.

Thanks in advance!
-tdiggity

p.s. what's the standard 3 prong outlet called? NEMA xx-xx
The 120v version is 5-15. (See Wikipedia article.) RV supply websites may have adapters.
 

markb1

Active Member
Feb 17, 2012
3,031
638
San Diego, CA
Thanks. I didn't think it was possible, but I thought i'd ask anyway.

I'll just have the electricians wire up both! For all you condo owners, it's something to think about because what if your 12v battery dies.....or you could power a vaccum cleaner :p

Sure, it's possible, if not advisable. You just have to have a 15- or 20-amp breaker in between the 14-50 and the 120V receptacle, and use the appropriate gauge wire. But you wouldn't want to run anything off the 120V outlet wire your car is charging. Not sure if that's legal, but it would work.
 

tdiggity

Member
Oct 3, 2012
725
4
Bay Area, CA
Sure, it's possible, if not advisable. You just have to have a 15- or 20-amp breaker in between the 14-50 and the 120V receptacle, and use the appropriate gauge wire. But you wouldn't want to run anything off the 120V outlet wire your car is charging. Not sure if that's legal, but it would work.

Probably won't pass inspection. Since I'm in a condo, they won't let this slide.
 

efxjim

Member
Jan 18, 2011
231
29
Glendale, CA
Have them install a 5-20 outlet. It looks and works just like a standard outlet but can take a 20A plug. That plug has 1 vertical and 1 horizontal prog. You can then safely pull a little more current from it.
 

mknox

Well-Known Member
Aug 7, 2012
10,103
1,866
Toronto, ON
Is it possible to step down a NEMA 14-50 outlet to the standard 3 prong outlet? I'm having a port installed in my condo and figured that I would also install a standard outlet just in case I need to do 120v stuff. But, if I can step the 14-50 down then I wouldn't have to get this installed.

Thanks in advance!
-tdiggity

p.s. what's the standard 3 prong outlet called? NEMA xx-xx

Yes, with one of these.

NEMA specs here.
 

gregincal

Active Member
Oct 26, 2012
3,763
2,294
Santa Cruz, CA
Oh well, they do have one. I figured you could do it with a built in 15 amp breaker, but fiddly. I didn't think of just having a 15 amp fuse. Much simpler.
 

FlasherZ

Sig Model S + Sig Model X + Model 3 Resv
Jun 21, 2012
7,024
1,013
As noted, it is a violation of NEC to mismatch a receptacle and breaker size, so you can't just tie a 15A receptacle on the 50A circuit. The only exception permitted is that 15A receptacles are permitted on 20A circuits as long as the wiring is sized appropriately (12 AWG).

As for mknox's device, it is legal in Canada only and is not UL-listed for use in the US, although I will argue it is safe to use in the US... Just keep in mind, as I warn with everything else, should you use a device that is not UL listed, in some/most cases your insurance company can legally refuse to pay a claim if your house burns down, regardless of whether that device caused the fire. Do not use any "home-made" adapter or device that does not provide over-current protection for the receptacle size you're stepping down to.
 
Last edited:

tdiggity

Member
Oct 3, 2012
725
4
Bay Area, CA
Thanks. Since the installation of the 14-50 port is such a pain for me (Condo), I'm going to have them install a 5-15 port at the same time. The cost is negligible compared to the 14-50.
 

TEG

Teslafanatic
Aug 20, 2006
21,717
8,682
Another approach:
Amazon.com: Conntek RV Y Adatper with 50 Amp Male Plug To RV 30 Amp and 15/20 Amp Female Connector (3-Feet): Sports Outdoors
413IIDn-7wL.jpg
 
  • Informative
Reactions: FlatSix911

mknox

Well-Known Member
Aug 7, 2012
10,103
1,866
Toronto, ON
One additional problem, though. Such a thing exists in Canada, but I'm not sure it's sold in the US.

I just posted the first link I found, but upon further Googling, it does appear to be a Canada only thing. It is CSA approved, and generally CSA and UL approvals are considered equivalent. I've seen bins full of these at my local Home Depot, Lowes etc.

A NEMA 14-50 is a 120/240 volt outlet (240 volts leg to leg and 120 volts from each led to neutral). All they're doing here is picking up one leg plus the neutral and fusing it at 15 amps. Seems perfectly safe to me...
 

FlasherZ

Sig Model S + Sig Model X + Model 3 Resv
Jun 21, 2012
7,024
1,013
A NEMA 14-50 is a 120/240 volt outlet (240 volts leg to leg and 120 volts from each led to neutral). All they're doing here is picking up one leg plus the neutral and fusing it at 15 amps. Seems perfectly safe to me...

I would concur that it is safe to use this device you posted and it poses very little risk. That said, I just warn everyone of the insurance issues associated with using a device that is not compliant to NEC within the US -- it's the same as building your own adapter/extension cord.

On the other hand, what TEG just posted may not be as safe and may pose a risk. While it is UL-listed, it is UL listed as an RV adapter cord only. It doesn't say whether it's fused or not (Conntek's site gives a 404 for the spec sheet) and that would present a safety hazard if some load went wonky.
 

mknox

Well-Known Member
Aug 7, 2012
10,103
1,866
Toronto, ON
On the other hand, what TEG just posted may not be as safe and may pose a risk. While it is UL-listed, it is UL listed as an RV adapter cord only. It doesn't say whether it's fused or not (Conntek's site gives a 404 for the spec sheet) and that would present a safety hazard if some load went wonky.

Yes, thanks for mentioning that. I took a quick peek at that adapter cord and didn't see any mention of fusing on the lower capacity plugs.
 

TEG

Teslafanatic
Aug 20, 2006
21,717
8,682
Yes, with one of these.

I can't see from the picture, but is the 240V side a NEMA 14-30 or NEMA 14-50 ?

14-50:
Cooper_Wiring_Devices_Nema_14-50_5754N.jpg


14-30:
DRYER-4-WIRE-OUTLET.JPG


The device said for "dryer plug" which is usually a 14-30. 14-50 is more of a welder/RV plug...
(Or maybe in Canada they use 14-50 more for dryer & range?)
 

FlasherZ

Sig Model S + Sig Model X + Model 3 Resv
Jun 21, 2012
7,024
1,013
That particular one is a 14-50 ("electric range"). There is also a model for a dryer that is available.

Simply plug gas range 110 Volt plug into the adapter, and then plug adapter into existing electric range 220 Volt outlet.
 

mknox

Well-Known Member
Aug 7, 2012
10,103
1,866
Toronto, ON
The device said for "dryer plug" which is usually a 14-30. 14-50 is more of a welder/RV plug...
(Or maybe in Canada they use 14-50 more for dryer & range?)

The one I linked to, as FlasherZ notes, is for a NEMA 14-50.

In Canada (as I assume is the case in the US), new electric ranges are typically 14-50 and new electric dryers are typically 14-30.
 

SeanTek

Member
Oct 15, 2012
88
11
California
Just thought I would give this thread a bump. Any updates? Did the Woods Gas Range Adaptor or the Conntek 14963 RV Y Adapter work out for you (as in, no reported deaths)? :tongue:
 

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