Some questions about 14-50 receptacles

[Villainthrpist]

I'm not going to necessarily disagree with you on this, but I do feel that it is better that you know about the issue. After all, if you were to change your mind and decide to live there longer, or it turned out you did store volatile chemicals (paint, solvents, etc...) you might make a different decision.

I appreciate you bringing it my attention.

 

[M3BlueGeorgia]

I'm looking to get a NEMA 14-50 receptacle installed and had a few questions, if anyone can help out. I'm looking to disconnect a wall heater right next to my garage and use that line to power the receptacle. It is powered by a 240V 20A breaker. The heater is the only thing that is on this circuit. I understand 20A is low for charging but it is better than 120v.

1. The Mobile Connector accepts a maximum current of 32A. Does this mean that it can accept lower amperages?
2. I don't know what the gauge is of the wire that is currently being run from the breaker to the wall heater. Is there a chance that the wire is not to spec for the receptacle?
3. The Hubble 14-50 receptacle I am looking at says it's rated for 50A. Do I need a breaker that is also rated for 50A or is it fine that the breaker output is less than the receptacle?

I ordered a wall connector to install in the garage but I am in a rental and the electrician quoted me $1k to disconnect the wall heater and run about 25ft of wire through wire track into the garage and connect the WC. I'm only going to be in this place for another year & 1/2 so the cost didn't seem to make sense, only to have to pay to get it disconnected when I leave and the set up again at my next residence.

First recommendation is to get a 6-20 adapter from Tesla and use the existing outlet and see if that's good enough.

Unless you have a long daily commute, it's probably all you need. Good for about 13 mph

 

[Rocky_H]

First recommendation is to get a 6-20 adapter from Tesla and use the existing outlet and see if that's good enough.

Sooo you just skipped reading the thread? There is no existing outlet, and the wall connector is already installed now.

 

[Eric33432]

Is that to electrical code anywhere? To do that, you would have to convert the white neutral wire to a hot wire and use the unshielded ground wire as neutral. It would work electrically, but I wouldn’t confess to anyone that I did that.

I realize this has been covered above, and OP already has the wall connector installed, but I write the below for others that may come across this.

Tesla mobile connector or wall connector do not require neutral.

It is common for appliances that are strictly 240 volt, like the Tesla connectors, to use two conductor, with ground, cable.

Also, if you can it is a really good idea to repurpose a dedicated 120 volt garage outlet to a NEMA 6-15 (15 amp circuit with 14 AWG wire) or NEMA 6-20 (20 amp circuit with 12 AWG wire). Wish I had thought of that.

But be damned sure that 120 volt outlet in the garage is a dedicated outlet (no other outlets on the same circuit). And be sure to install a 2 pole 15 or 20 amp (as appropriate for the wire size) GFCI breaker for this circuit.

Best to have electrician do this, but you may need to ask an electrician if something like this can be done.

 

[Eric33432]

You can use various adapters and you can get a 50A extension cord. The cord is very heavy, it’s similar to a garden hose in diameter. Mine I think is 30 feet. Then one can add various adapters to the end. I have an adapter that goes to a modern clothes dryer outlet. With the extension and the adapter I can charge from a 240V household dryer outlet. I believe I get 15 or so miles of charge per hour that way, but it’s been a while.

I realize this has already been covered, and the OP already has installed a TWC, but I post this for anyone who may have a similar situation that comes across this.

You will not be happy charging from 120 volts unless you drive just a little.

If your apartment has a dryer, consider using that. Just don't use the dryer at the same time you charge the car.

You can get an adapter cable from Amazon:

3 Pin Dryer outlet:

Amazon.com

4 Pin Dryer outlet:

Amazon.com

I use the dryer outlet at a vacation property I go to. If the dryer is out of reach from your car using the 20 foot long Tesla Mobile Connector, you can get the correct size extension cord from Amazon (only need a 30 amp extension cord, which is still a heavy cord) with the correct plug (some dryer outlets are 3 pin and some are 4 pin), and use that with the Tesla mobile connector. You would order the correct Tesla adapter -- NEMA 10-30 for the 3 pin or the NEMA 14-30 for the 4 pin dryer outlet.

NEMA Adapter Bundle

Maximize your charging options with the NEMA Adapter Bundle. Simply attach the appropriate adapter to your Mobile Connector, plug into the corresponding outlet and begin charging. With all seven Gen 2 NEMA Adapters in one convenient storage bag, you can charge at any available outlet, at home or...

shop.tesla.com

Edit: I would only do the above for temporary or occasional use; it is not something that would be good for a permanent situation.

 

[exxxviii]

Tesla mobile connector or wall connector do not require neutral.

Yep, this was pretty thoroughly discussed about 40 posts ago….

As were all the OP’s constraints and available circuits. He has very limited options, so the thread focused on best available options within the available options.

 

[Eric33432]

Yep, this was pretty thoroughly discussed about 40 posts ago….

As were all the OP’s constraints and available circuits. He has very limited options, so the thread focused on best available options within the available options.

Right, but others may come across this and be able to use some of the ideas I and others have suggested.

 

[exxxviii]

Right, but others may come across this and be able to use some of the ideas I and others have suggested.

Or they’ll read the prior 50 posts. This was an interesting use case and discussion. The OP got the circuit installed and has been charging for a week.

 

[Eric33432]

Or they’ll read the prior 50 posts. This was an interesting use case and discussion. The OP got the circuit installed and has been charging for a week.

I give up. Not worth the negativity.

 

[ai4px]

I'm looking to get a NEMA 14-50 receptacle installed and had a few questions, if anyone can help out. I'm looking to disconnect a wall heater right next to my garage and use that line to power the receptacle. It is powered by a 240V 20A breaker. The heater is the only thing that is on this circuit. I understand 20A is low for charging but it is better than 120v.

1. The Mobile Connector accepts a maximum current of 32A. Does this mean that it can accept lower amperages?
2. I don't know what the gauge is of the wire that is currently being run from the breaker to the wall heater. Is there a chance that the wire is not to spec for the receptacle?
3. The Hubble 14-50 receptacle I am looking at says it's rated for 50A. Do I need a breaker that is also rated for 50A or is it fine that the breaker output is less than the receptacle?

I ordered a wall connector to install in the garage but I am in a rental and the electrician quoted me $1k to disconnect the wall heater and run about 25ft of wire through wire track into the garage and connect the WC. I'm only going to be in this place for another year & 1/2 so the cost didn't seem to make sense, only to have to pay to get it disconnected when I leave and the set up again at my next residence.

You can turn the maximum charge rate down on the screen of Tesla and it will remember that setting at that location.

You can also buy a NMEA 6-20 plug and the mobile charger will force the car to lower amps.

 

[SageBrush]

You can turn the maximum charge rate down on the screen of Tesla and it will remember that setting at that location.

My Bold. I strongly suggest NOT relying on the car for this. Settings can be forgotten or lost or changed. Get the Tesla adapter, it is cheap insurance against damage and fire.

 

[Rocky_H]

My Bold. I strongly suggest NOT relying on the car for this. Settings can be forgotten or lost or changed. Get the Tesla adapter, it is cheap insurance against damage and fire.

And this is not too unusual that the car will be off with its GPS location. I've had this a few times in the last few months where I got home and pulled into my driveway and was wondering why it didn't auto-open my garage door. The skies were thick and rainy and overcast, so the car wasn't getting a good GPS signal and thought my car was a block or two away in my neighborhood. And it also didn't use my lowered amp setting because of that.

 

[THEbuz]

You cannot pull more than 20A through your existing wire and in fact the most you can use on that connection is 16A (there is an 80% rule for continuous load items) so you need a new wire. It is extremely unlikely the wire is rated for the kind of loads EV charging requires.

$1,000 may be a reasonable price based on location of the breaker box.

So then as to hardware cost, in addition to the wire and running it:

The Wall Connector is about $400 and the breaker is about $15. If you install a 50A circuit you will charge at 40A and if you install a 60A circuit you will charge at 48A. It is very easy to remove the wall connector and take it with you (easy DIY). Your sunk case is just $15 for the breaker,

The mobile connector is $230, the Hubbell NEMA 14-50 outlet is about $80, you will need a GFCI breaker at about $150, and some sort of cable management system for say $35, this total $492. You will be limited to a 32A charge rate (mobile connector limit.) It is of course easy to take the mobile connector with you, but the outlet and breaker costs are a sunk costs.

If you do not do one of the above, what other option(s) are you considering?

I had an electrician install a 60A breaker to my existing electrical panel at home. Obviously, I can draw up to 48A from my 60A dedicated circuit to charge my TESLA using my TESLA Wall Connector, which my electrician also installed. In addition, I had my electrician install a NEMA 14-50 receptacle (outlet) on the wall right next to my TESLA Wall Connector. Both are installed on the wall adjacent to my (roll-up) garage door (on the inside). I had it installed that way because I wanted to have the NEMA 14-50 receptacle available for additional EV charging, possibly using my (or someone else's) TESLA Mobile Connector (with the NEMA 14-50 adapter), whether charging while parked inside my garage or just outside my garage in my driveway.

QUESTION 1: Is my TESLA Mobile Connector a Gen2 connector? I am assuming that it is. (I purchased my TESLA Mobile Connector in NOV2022 when I took delivery of my 2023 Model Y.)

QUESTION 2: Since I can, technically, draw up to 48A from my NEMA 14-50 receptacle (outlet), am I in danger of blowing out or frying my TESLA Mobile Connector when plugging into my NEMA 14-50 receptacle (outlet), since it draws up to 48A? Is the TESLA Mobile Connector capable of automatically restricting the amperage it draws, or will I need to have my electrician come back and rewire my NEMA 14-50 receptacle (outlet) to its own dedicated 32A circuit to ensure that I don't fry my TESLA Mobile Connector when charging using the TESLA Mobile Connector from my NEMA 14-50 receptacle (outlet)?

 

[THEbuz]

My Bold. I strongly suggest NOT relying on the car for this. Settings can be forgotten or lost or changed. Get the Tesla adapter, it is cheap insurance against damage and fire.

What do you mean by "TESLA adapter"? To what are you referring? Thanks

 

[Sophias_dad]

I had an electrician install a 60A breaker to my existing electrical panel at home. Obviously, I can draw up to 48A from my 60A dedicated circuit to charge my TESLA using my TESLA Wall Connector, which my electrician also installed. In addition, I had my electrician install a NEMA 14-50 receptacle (outlet) on the wall right next to my TESLA Wall Connector. Both are installed on the wall adjacent to my (roll-up) garage door (on the inside). I had it installed that way because I wanted to have the NEMA 14-50 receptacle available for additional EV charging, possibly using my (or someone else's) TESLA Mobile Connector (with the NEMA 14-50 adapter), whether charging while parked inside my garage or just outside my garage in my driveway.

QUESTION 1: Is my TESLA Mobile Connector a Gen2 connector? I am assuming that it is. (I purchased my TESLA Mobile Connector in NOV2022 when I took delivery of my 2023 Model Y.)

QUESTION 2: Since I can, technically, draw up to 48A from my NEMA 14-50 receptacle (outlet), am I in danger of blowing out or frying my TESLA Mobile Connector when plugging into my NEMA 14-50 receptacle (outlet), since it draws up to 48A? Is the TESLA Mobile Connector capable of automatically restricting the amperage it draws, or will I need to have my electrician come back and rewire my NEMA 14-50 receptacle (outlet) to its own dedicated 32A circuit to ensure that I don't fry my TESLA Mobile Connector when charging using the TESLA Mobile Connector from my NEMA 14-50 receptacle (outlet)?

Yes, your Tesla Mobile Connector(usually called a UMC, universal mobile connector) would be a Gen2.

Your UMC can only ever draw 32A, and there's also a thing called a Corded Mobile Connector(has a hardwired 14-50 plug!) that could draw 40A from a 14-50 .

There are tons of problems with your install. Connecting the 14-50 in parallel with the HPWC is a significant violation of the NEC. It will guaranteed trip the breaker if you try to use both at the same time. It will not damage either the UMC or the HPWC, but you won't be charging at all on either once the breaker trips. Violation 1: Supplying a 14-50 with cable/breaker good for 60A is not allowed. The receptacle itself isn't rated to handle that much power. Violation 2: EV charging circuits are supposed to be dedicated to one device: Violation 3(similar to 2): 14-50's are required to be alone on the circuit. Violation 4: EV outlets are supposed to be GFCI breaker protected.

The circuit for your 14-50 should be dedicated, and at least rated to 40A(to get 32A out of it), and have a GFCI breaker feeding it. If its wired/breakered for 40 instead of 50A, it should be labeled(at the receptacle) as such.

Sadly, UMCs don't power share, so you can't just put a 60A subpanel in place of your HPWC and feed both devices from that. It'd be a major stretch, but you could still do that as long as you specifically decreased the draw of the HPWC to 16A by hand, in the car, whenever the UMC was in use.

Your electrician should go back to electrician school, unless they are really your 'relative that's good with elecricity' . I hesitate to ask what type of conductors are feeding your 60A HPWC. Maybe I shouldn't hesitate, since if they have to be replaced anyway you might as well go whole-hog and put a 100A subpanel in the garage.

 

[Rocky_H]

In addition, I had my electrician install a NEMA 14-50 receptacle (outlet) on the wall right next to my TESLA Wall Connector.

What EXACTLY do you mean here? The answer will determine if what you have is totally fine, or is very very bad, as @Sophias_dad explains in detail. He assumes that it means that you have BOTH the wall connector and the 14-50 outlet connected onto the SAME 60A circuit. If so, that would be Very Bad (TM). But from the wording, I'm not sure if that's what you're describing. Each one needs to be on a dedicated circuit, so if you just meant that you also got a 14-50 outlet installed on its own separate circuit with separate breaker (either 40 or 50 amp), then that would be OK.

 

[mspohr]

The circuit for your 14-50 should be dedicated, and at least rated to 40A(to get 32A out of it), and have a GFCI breaker feeding it.

I'm not sure about the GFCI.
I've had several 14-50 installed recently in new construction and no GFCI and passed inspection.
Is this something new in NEC?

 

[Rocky_H]

I'm not sure about the GFCI.
I've had several 14-50 installed recently in new construction and no GFCI and passed inspection.
Is this something new in NEC?

It varies a little by state which version they are on, but since NEC 2017, yes, it's a bit new, that any outlet being installed for the purpose of EV charging must have a GFCI.

 

[THEbuz]

Yes, your Tesla Mobile Connector(usually called a UMC, universal mobile connector) would be a Gen2.

Your UMC can only ever draw 32A, and there's also a thing called a Corded Mobile Connector(has a hardwired 14-50 plug!) that could draw 40A from a 14-50 .

There are tons of problems with your install. Connecting the 14-50 in parallel with the HPWC is a significant violation of the NEC. It will guaranteed trip the breaker if you try to use both at the same time. It will not damage either the UMC or the HPWC, but you won't be charging at all on either once the breaker trips. Violation 1: Supplying a 14-50 with cable/breaker good for 60A is not allowed. The receptacle itself isn't rated to handle that much power. Violation 2: EV charging circuits are supposed to be deficated to one device: Violation 3(similar to 2): 14-50's are required to be alone on the circuit. Violation 4: EV outlets are supposed to be GFCI breaker protected.

The circuit for your 14-50 should be dedicated, and at least rated to 40A(to get 32A out of it), and have a GFCI breaker feeding it. If its wired/breakered for 40 instead of 50A, it should be labeled(at the receptacle) as such.

Sadly, UMCs don't power share, so you can't just put a 60A subpanel in place of your HPWC and feed both devices from that. It'd be a major stretch, but you could still do that as long as you specifically decreased the draw of the HPWC to 16A by hand, in the car, whenever the UMC was in use.

Your electrician should go back to electrician school, unless they are really your 'relative that's good with elecricity' . I hesitate to ask what type of conductors are feeding your 60A HPWC. Maybe I shouldn't hesitate, since if they have to be replaced anyway you might as well go whole-hog and put a 100A subpanel in the garage.

I’m not an electrician (as I said, I didn’t install it), but I’ve shared your comment with my electrician (who is NOT a TESLA owner—but still a good guy ), so let’s see if he responds. I’ll post it here if he does. He installed that NEMA 14-50 at my request. If it was a code violation, then I’m confident he would have advised me accordingly.

Also, I don’t have to restrict my amperage in the TESLA app to 16A when “double-charging” but rather I must restrict my amperage in the TESLA app to 24A. I have a 60A circuit from which I can draw 48A, so splitting that capacity with the UMC with each drawing 24A will work just fine.

 

[THEbuz]

What EXACTLY do you mean here? The answer will determine if what you have is totally fine, or is very very bad, as @Sophias_dad explains in detail. He assumes that it means that you have BOTH the wall connector and the 14-50 outlet connected onto the SAME 60A circuit. If so, that would be Very Bad (TM). But from the wording, I'm not sure if that's what you're describing. Each one needs to be on a dedicated circuit, so if you just meant that you also got a 14-50 outlet installed on its own separate circuit with separate breaker (either 40 or 50 amp), then that would be OK.

Nope. Both are drawing from the same circuit. So far, I have not had to use the TESLA Mobile Connector. Should I ever need to use both concurrently, then I would throttle back the amperage drawn from my TESLA Wall Connector to 24A in the TESLA mobile app, allowing 24A to be drawn from the TESLA Mobile Connector concurrently.

What’s so bad about that?