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Installing a NEMA 14-50 with 60amp breaker

Installing a NEMA 14-50 with 60amp breaker

Hello,

I just installed a NEMA 14-50 outlet with #6 wires and a 60amp breaker.
I realized that the majority of the videos in youtube are showing a 50amp breaker instead.

Do any of you know if the 60amp breaker would not work?

riccifrance | 21/11/2018

Hello,

I just installed a NEMA 14-50 outlet with #6 wires and a 60amp breaker.
I realized that the majority of the videos in youtube are showing a 50amp breaker instead.

Do any of you know if the 60amp breaker would not work?

roger.klurfeld | 21/11/2018

The only difference is that 8 gauge wire is not up to code for 60 amps. Since you have 6 gauge wire you should not have a problem. But. using a 14-50 outlet you will charge your model 3 at 32 amps, the limit of the charger in the car unless you get a hard wired wall connector. So it won't charge your car any faster.

dwakelee | 21/11/2018

A NEMA 14-50 outlet is rated at 50A max. By using a 60A breaker, there is a risk that a short circuit or overcurrent will overheat the outlet / plug / wiring before the breaker trips.

The breaker must be sized to protect the weakest link, which in this case is your NEMA 14-50 outlet. Change the breaker to 50A, or direct wire to a Wall Connector and lose the 14-50 outlet.

frisbee912 | 21/11/2018

I have thought about the exact same up for flexibility, but did not proceed. My understanding is that 14-50 would be oversized by 60 amp breaker and it would not be properly protected.

Carl Thompson | 21/11/2018

@roger.klurfeld:
"... your model 3 at 32 amps, the limit of the charger in the car ..."

Actually the charger in the Model 3 can charge faster than 32A. It's the mobile connector cable they give you that's limited to 32A.

I have a 3rd party EVSE cable plugged into a 14-50 and my Model 3 charges at 40A.

riccifrance | 21/11/2018

Would I be OK to downsize to a 50 amp breaker but still using the six gauge wires?

dmaini | 21/11/2018

yes that would work.. riccifrance

Passion2Fly | 21/11/2018

@riccifrance
yes, keep the #6 wire! In the future, if you ever want to install a Tesla Wall charger, all you have to do is remove the NEMA 14-50 outlet and switch the breaker to 60 Amps. You can now take FULL advantage of your 48 Amps on-board charger!

riccifrance | 21/11/2018

Awesome. Thanks everyone!

JAMESLHARWOOD | 21/11/2018

Personally I would by a Tesla HPWC (I did) and use that 60amp breaker and #6 wire to wire that HPWC. Then you can leave you mobile connector in the trunk all the time and you can now charge at 48amps vs. the 32amps that the Mobile connector will max out at.

Right now your house is wired for 60amp (48amp max constant use) and your car has on board charger of 48amps constant, but the week link is that mobile connector that has a max charge of 32amps.

Also the HPWC can be found on ebay and craigslist for around 400.00 out the door. I picked mine up brand new in unopened box for 400 on craigslist and probley saved around 150.00 vs. buying straight from Tesla website. Many people get them as referral gifts after they already had one and choose to sale it and willing to negotiate due to them getting it for free to begin with and the flood of them now for sale for that same reason.

riccifrance | 21/11/2018

@Jameslhardwood. Not sure if I can justify $400-500 wall mount connection cable. I don’t think is really necessary at least not to gain 16 MPH extra charging.
I can charge up the vehicle overnight and it will be ready by the time I need it. For traveling, I can use supercharging station or bring my cable. I’m a frugal guy.
Who knows, maybe in the future I’ll be switching to the Tesla wall mount cable.

JAMESLHARWOOD | 21/11/2018

I get it, but I figured if you went threw the trouble and expense for installing the 6 guage wire and outlet, I figured that cost more then the charger for 90% of the people.

riccifrance | 21/11/2018

@jameslhardwood. I did it myself for a total of $58 and completed in about 50 minutes. I was also able to return the 60 amp breaker for a full refund.

Carl Thompson | 21/11/2018

I like my 3rd party EVSE approach because it both charges faster than the mobile connector and can also be used for other EVs. (I also have a RAV4 EV and I have friends with non-Tesla EVs.)

Carl Thompson | 21/11/2018

It's also cheaper than the wall connector.

Passion2Fly | 21/11/2018

@Carl,
Yes, I agree. I would probably install a "standard" wall charger just in case friends come over or I decide to buy a non-Tesla EV in the future...

riccifrance | 21/11/2018

@Carl Thompson. How much does the EVSE cost?

Carl Thompson | 21/11/2018

riccifrance

@Carl Thompson. How much does the EVSE cost?

Here is the one I bought. Works quiet and cool, charges at 40A and plugs into a 14-50 so it's portable and easy to switch to something else in the future. Definitely recommend.

https://smile.amazon.com/gp/product/B071GM7GQZ

riccifrance | 21/11/2018

@Carl Thompson.

Thanks for the info!

sheldon.mike1010 | 21/11/2018

#Carl Thompson:
I have a 14-50 receptacle and the Tesla Mobile Connector that came in the frunk kit.
How is the Amazon one you bought different from my setup?

JAMESLHARWOOD | 21/11/2018

@sheldon
The one that came in your Trunk only works on Tesla's.
These guys above assume after you buy a Tesla you would want to buy a different EV car or that you would even associate with people who do.

Carl Thompson | 21/11/2018

@sheldon

What @JAMESLHARWOOD said. Also, the Tesla supplied Mobile Connector will only charge at up to 32A but mine will charge faster (up to 40A). It also allows me to keep the Mobile Connector in the car at all times in case of the improbable possibility that I might need it while traveling.

kevin_rf | 21/11/2018

One advantage of 6awg over 8awg is the wire has lower resistance, so lower line losses as you charge. Keep the 6awg.

ODWms | 21/11/2018

I installed a NEMA 14 50 with 50 amp breaker and 6 awg wiring right below my 200 amp panel in the garage. I thought it was the best balance between cost and utility. As mentioned it can charge up all the way overnight, even from zero. Some others have specific need for the Tesla wall charger that would make sense for them. It matters little to me whether my car finishes charging at 5:30 in the morning or 3:15 am. I'm asleep either way.

riccifrance | 22/11/2018

@ODWms
Right on point.
$500 for the Tesla wall mount is a little too extreme. Yes it looks cool but I don’t need it right now.

john.love | 20/05/2019

If your installing a plug for the mobile charger - better review if you need a GFI circuit breaker - code seems to require it for a plug used for EV's (at least the way its interpreted in the peoples republic of King County Washington).

NEC-625.54. Ground-Fault Circuit-Interrupter Protection for Personnel

All single-phase receptacles installed for the connection of electric vehicle charging that are rated 150 volts to ground or less, and 50 amperes or less shall have ground-fault circuit- interrupter protection for personnel.

Atoms | 20/05/2019

If you have a fire, forget the insurance company covering you. This is not to code. The circuit breaker must be 50A or less because your outlet is rated for 50A. You better have an electrician inspect and certify it is to code. It is also in your interest to have it permitted. If permitted and installed to code, your fire insurance will be worth what you pay for it.

kalalp | 20/05/2019

NEC-625.54. Ground-Fault Circuit-Interrupter Protection for Personnel
All single-phase receptacles installed for the connection of electric vehicle charging that are rated 150 volts to ground or less, and 50 amperes or less shall have ground-fault circuit- interrupter protection for personnel.

The key words here are "rated 150 volts to ground or less". A Nema 14-50 plug is rated 240 volts. Therefore is exempt from the GFCI protection. Lot of FUD on this. Seen it posted in various places.

darrin.wineberg | 12/09/2019

Hey guys. sorry to resurrect a dead thread, but i was wondering since the travel charger only charges at 32A, doesn't it make sense to put a 40A breaker instead? it can do 80% of the 40A which is 32A so putting a 50A would be a waste right? unless you wanted say a 40A 3rd part charger i guess. If you ever wanted the Tesla wall charger you would need to go to 60A anyway to get the full 48A. Just food for thought. Thanks,

andy.connor.e | 12/09/2019

Yes what you say makes sense. A larger breaker is more of a future planning if you want to get a faster charger at some point. 40A is fine.

CJCAMCD | 12/09/2019

I'm using a 40A breaker on my Nema 14-50 and charging at 32A, which is all the mobile charger will charge at anyway. It's performing great!

radean84 | 12/09/2019

I have a 260v50a plug and my Model 3 limits it to 244v32a which provides between 28-33 mi/hr charging

Tronguy | 12/09/2019

@darrin.wineberg: It's like this. First off, you're only saving a couple of bucks by putting in a smaller gauge wire and a smaller breaker (40A). Second: You may know that you've done this, but the person who eventually moves into the house in 15 years won't, and that's a good way for things to end up in tears. Third, at least in NJ, there's a requirement that the electrical inspector at least look over the plans, and, for reason #2, they won't like your idea.
The general safety idea is that the breaker, the wire to the outlet, and the outlet itself all be rated at the same number, and the actual steady-state load is at 80% of that number.
This is why 15A 120 VAC outlets are all hooked to 15A breakers and max load on such an outlet is 12A (80% of 15A).
There is a rumor that the national electrical code recognizes as legit certain installations that use a NEMA14-50 with a 40A breaker. I don't know if such an installation would require some kind of label to warn the unwary. But it's given out that this is the reason that Tesla's won't draw more than 32A on a NEMA14-50, since they don't know if there's a 40A or 50A circuit backing up the connector, and they opt for safety as a result.

andy.connor.e | 12/09/2019

I have no idea what @Tronguy is talking about. 50A breaker for max 32A current draw is overkill. Code requires that the wire size is 125% of your minimum circuit amperage, which being 32A, means that you need 8 AWG wire. If your run is over 150ft, you will need 6 AWG wire.

Do not undersize your wire for cost savings, as the smaller wire you get the higher electrical losses you will experience within the wires which will cost you more in electricity over time than you saved in material costs.

40A breaker is fine. If the difference in cost between the 50A and 40A breaker is dollars, just get the 50A for ease of future expansion.

andy.connor.e | 12/09/2019

I had the terms backwards, its 125% of full load current which is 32A here. 40A would be the minimum circuit amperage, or the current you size the wires at. Hope this helps.

Frank99 | 12/09/2019

tronguy is correct.
It's not that a 50A breaker is overkill for 32A current draw; it's that it's the CORRECT breaker to install for a 14-50 outlet. Although, Yes, the NEC allows a 14-50 on a 40A circuit ( https://diy.stackexchange.com/questions/103120/40-amp-range-into-50-amp-... ).

Home Depot sells 125' of 6/2 Romex for $150, and 125' of 8/2 Romex for $104. The breaker is the same price whether 50A or 40A. So, at retail prices we're talking $50 difference in the cost of installing AWG 6 v. AWG 8 on a 100' run. Assuming you have an electrician do the install, this is in the noise.

If you decide to install AWG 8 and a 40A breaker, it means that 5 years down the line when you trade for a different EV that uses a J1772 charger (might even be a Tesla!), you'll limit yourself 32A, even though your new EV may support higher charging rates (J1772 is good up to 80A). It's a very short sighted decision when your rationale is "It's Overkill!".

IMHO, install a 50A circuit terminated with a 14-50. It's what the UMC is designed to plug into, and what you or anyone who lives in the house 10 years from now will expect to be behind that 14-50 outlet. If your run is short, consider installing even higher-capacity wiring (80A or 100A) with the 50A breaker and 14-50 outlet, because your next EV might be a Pickup, and might need the higher amperage to fully charge overnight. Changing out a breaker and outlet is a lot easier than changing the wiring in the walls.

andy.connor.e | 12/09/2019

I missed the part that hes trying to install a 50A outlet. If you're installing a 50A outlet, inspector is going to want to see a 50A breaker. Sorry for the confusion.

andy.connor.e | 12/09/2019

And also if cost is not a concern to you, install the better future proof option. If you sell your house, the higher amperage will be more appealing to a new owner.

kaffine | 12/09/2019

Quote:

kalalp | May 20, 2019
NEC-625.54. Ground-Fault Circuit-Interrupter Protection for Personnel
All single-phase receptacles installed for the connection of electric vehicle charging that are rated 150 volts to ground or less, and 50 amperes or less shall have ground-fault circuit- interrupter protection for personnel.

The key words here are "rated 150 volts to ground or less". A Nema 14-50 plug is rated 240 volts. Therefore is exempt from the GFCI protection. Lot of FUD on this. Seen it posted in various places.

----------------------------------------------------

Single phase 240V is only 120V to ground. Hot leg to Hot leg is 240 but either leg to ground is only 120V. So a NEMA 14--50 is not exempt since it is only rated 125V to ground from either hot leg.

@ Tronguy : A 50 amp outlet protected by a 40 amp breaker is code compliant in most places. Also residential is allowed to use 20 amp breaker with 15 amp outlets as long as there is more than one outlet on the circuit and the normal outlet is a duplex which counts as two. In commercial buildings if it is a 20 amp circuit it has to have a 20 amp outlet. However is you open up most 15 amp outlets they have the same internals as 20 amp it is just the front cover that is different.

@Frank99

14-50 outlets need 3 conductor plus ground not 2 conductor plus ground. 14-50 require a neutral.