Tesla Wall connector with 14-50 NEMA plug

[android04]

The power electronics in the on board charger that converts 240v (or 120v) AC to the nearly 400v DC needed to charge the battery. The reported behavior has been that charging at or below 16a uses one charging circuit, Charging between 16a and 32a splits the load across two of them and >32a (in cars that support it) splits the load across all three. If I had to guess at the reasons WHY it would be programmed that way, I would say that it comes down to efficiency. The power electronics are probably less efficient at low amperages, so it makes more sense to run one circuit at 16a than two at 8a or three at 5.33a.

This is the exact behavior I observed a year ago when I was playing around with Service Mode in my Model 3 (where you can see the current in each individual phase module as well as a lifetime kWh counter that shows how much each has been used).

I have a HPWC that can charge my LR RWD at up to 48A, and knowing that my car has 3 different phase modules for charging that can handle 16A each I was curious on how it divides the current between them. So I adjusted the charge current from 48A down to the minimum (I believe it was 8A) little by little to see the current between the 3 modules. 0-16A was on one phase. 17-32A was split evenly between two phase modules. 33-48A was split evenly between three phase modules. So if you want current to be evenly split between two or three modules to limit stress on them and equally wear them out, avoid 16A, 32A (and use 33A if your car and EVSE can handle it), and 48A (go a little lower if you want to avoid maxing out the phase modules, like 42A) settings. For example, looking at a picture I took of setting my charge current to 34A, each of the 3 phase modules showed a current of 11.4A at 235V in the Service Mode screen.

 

[ElectricNerd]

I've been contacting a few local electricians who specialize in installing the Tesla Wall Connector and one told me that I cannot use a NEMA 14-50 plug with it because Tesla didn't design it to work that way. I have an existing NEMA 14-50 that a current third party charger is using. The existing 50a breaker is not a GFCI breaker. This electric company told me I would need to replace it with a GFCI for the Tesla Wall Connector. I thought the Wall Connector had an integrated GFCI and Tesla says not to use a GFCI breaker?

I honestly do not want to pay the $650+ for an electrician to come out, run a new 4/3 ROMEX to replace the 6/3 ROMEX should I choose to go with a 60a breaker instead of using the existing 50a breaker and 6/3 wiring, and on top of that use a GFCI breaker costing me even more.

Can I really not use the existing outlet? I guess I could replace the outlet with the Wall Charger itself and use the existing wiring, but then I don't have a place to mount the Wall Charger without leaving the hole where the outlet is now. It's in the wall using a remodel box.

 

[355rockit]

I've been contacting a few local electricians who specialize in installing the Tesla Wall Connector and one told me that I cannot use a NEMA 14-50 plug with it because Tesla didn't design it to work that way. I have an existing NEMA 14-50 that a current third party charger is using. The existing 50a breaker is not a GFCI breaker. This electric company told me I would need to replace it with a GFCI for the Tesla Wall Connector. I thought the Wall Connector had an integrated GFCI and Tesla says not to use a GFCI breaker?

I honestly do not want to pay the $650+ for an electrician to come out, run a new 4/3 ROMEX to replace the 6/3 ROMEX should I choose to go with a 60a breaker instead of using the existing 50a breaker and 6/3 wiring, and on top of that use a GFCI breaker costing me even more.

Can I really not use the existing outlet? I guess I could replace the outlet with the Wall Charger itself and use the existing wiring, but then I don't have a place to mount the Wall Charger without leaving the hole where the outlet is now. It's in the wall using a remodel box.

Not sure why the electrician is reluctant. My electrician installed the NEMA 14-50 outlet and I mentioned my plan to add a 14-50 plug to the wall connector and he had no issues. You can add the pigtail easily yourself like I did and use your outlet. I have mine running well for the past 3 years or so. See the video link I noted earlier in the thread. I did mine just like that. Just make sure you torque the wire connection bolts per the installation manual.

 

[JssonB]

I've been contacting a few local electricians who specialize in installing the Tesla Wall Connector and one told me that I cannot use a NEMA 14-50 plug with it because Tesla didn't design it to work that way. I have an existing NEMA 14-50 that a current third party charger is using. The existing 50a breaker is not a GFCI breaker. This electric company told me I would need to replace it with a GFCI for the Tesla Wall Connector. I thought the Wall Connector had an integrated GFCI and Tesla says not to use a GFCI breaker?

I honestly do not want to pay the $650+ for an electrician to come out, run a new 4/3 ROMEX to replace the 6/3 ROMEX should I choose to go with a 60a breaker instead of using the existing 50a breaker and 6/3 wiring, and on top of that use a GFCI breaker costing me even more.

Can I really not use the existing outlet? I guess I could replace the outlet with the Wall Charger itself and use the existing wiring, but then I don't have a place to mount the Wall Charger without leaving the hole where the outlet is now. It's in the wall using a remodel box.

You can use your existing outlet. If it was installed and inspected, you don't need to do anything with it. As for the wall connector, you have two options with using your 50amp breaker. Keep it and use your wiring and wire it directly to your wall connector and it will charge at 9.6kW's instead of 11.5kW's. Is that worth the extra cost to you?

Circuit breaker (amps)	Maximum output (amps)	Power at 240 volts (kilowatt)	Model S (mph)	Model 3† (mph)	Model X (mph)	Model Y (mph)
Wall Connector Technical details	Charge Speed Max miles of range per hour of charge*
60	48	11.5 kW	41	44	35	44
50	40	9.6 kW	34	37	29	37
40	32	7.7 kW	27	30	23	30
30	24	5.7 kW	21	22	17	22
20	16	3.8 kW	14	15	12	15
15	12	2.8 kW	10	11	9	11

�


Or you can use a 14-50 pigtail and wire it to the wall connector and then plug it into your existing 14-50 receptacle. I thought the wall connector had an option to add the 14-50 adapter, but it looks like that is only on the mobile connector.

I currently use my RV 14-50 for both mobile chargers using a NeoCharge splitter and it sure beats trying to stop one car and start the other at 11:00pm.

 

[3sr+buyer]

I've been contacting a few local electricians who specialize in installing the Tesla Wall Connector and one told me that I cannot use a NEMA 14-50 plug with it because Tesla didn't design it to work that way. I have an existing NEMA 14-50 that a current third party charger is using. The existing 50a breaker is not a GFCI breaker. This electric company told me I would need to replace it with a GFCI for the Tesla Wall Connector. I thought the Wall Connector had an integrated GFCI and Tesla says not to use a GFCI breaker?

I honestly do not want to pay the $650+ for an electrician to come out, run a new 4/3 ROMEX to replace the 6/3 ROMEX should I choose to go with a 60a breaker instead of using the existing 50a breaker and 6/3 wiring, and on top of that use a GFCI breaker costing me even more.

Can I really not use the existing outlet? I guess I could replace the outlet with the Wall Charger itself and use the existing wiring, but then I don't have a place to mount the Wall Charger without leaving the hole where the outlet is now. It's in the wall using a remodel box.

Since you are in Texas, the 2020 NEC applies.

In the 2020 NEC, a new outlet for EV charging must have GFCI protection. But it does not look like you are installing a new outlet, since you are either using the one that is already there, or replacing it with a hardwire setup. Seems like your options with a Tesla wall connector are:

1. Add a 14-50 plug and use it with the outlet, setting the wall connector to charge at 32A (if a 40A circuit) or 40A (if a 50A circuit).
2. Replace the 14-50 outlet with hardwiring to the wall connector, setting the wall connector to charge at 32A (if a 40A circuit) or 40A (if a 50A circuit).
3. Install a new 60A breaker and 60A circuit to hardware to the wall connector to charge at 48A. This may either replace the existing circuit with the 14-50 outlet, or be a completely new circuit, leaving the existing 14-50 outlet and circuit (if your main panel has that much capacity).

If you go with retaining the outlet, check that the contacts with the plug blades are brass and contact the full plug blades (look into the plug holes to see). There is at least one common model of 14-50 outlet where the contacts are steel and only contact half of the plug blades, resulting in higher resistance and heat. These outlets tend to be marginal at 32A charging; the risk of overheating becomes greater at 40A charging.

Between 1 and 2, the hardwire setup is probably safer, since there would be just one set of connections (wall connector to wires in the box) instead of three (wall connector to 14-50 plug, 14-50 plug in 14-50 outlet, 14-50 outlet to wires in the box) where a poor connection could cause trouble.

 

[ElectricNerd]

Main problem is the city I live in is very permit heavy. Even replacing a fence requires a permit. An above ground pool requires a permit.

I can do the work myself, but am curious if I’d be in any trouble if I did that. This is with the hardwire option.

I can certainly keep the 14-50 outlet and use that but the outlet is a big box brand. I have a Bryant but it’s finicky and I don’t trust it.

 

[stopcrazypp]

Main problem is the city I live in is very permit heavy. Even replacing a fence requires a permit. An above ground pool requires a permit.

I can do the work myself, but am curious if I’d be in any trouble if I did that. This is with the hardwire option.

Officially you would need a permit for hardwire. In California, home owners can do their own work and can get electrical permits for minor work that does not require plans (check your own local laws if this is allowed). Consequences for not getting one really depends on your local laws. The more lax ones, if they find out would just have to pay for the permit and inspection. More strict ones may have fines on top of that.

The bigger issue is if anything happens, your insurance can deny your claim. That's usually the biggest risk that most people gamble when they decide to do something without permit.

I can certainly keep the 14-50 outlet and use that but the outlet is a big box brand. I have a Bryant but it’s finicky and I don’t trust it.

 

[rpiotro]

I've been contacting a few local electricians who specialize in installing the Tesla Wall Connector and one told me that I cannot use a NEMA 14-50 plug with it because Tesla didn't design it to work that way. I have an existing NEMA 14-50 that a current third party charger is using. The existing 50a breaker is not a GFCI breaker. This electric company told me I would need to replace it with a GFCI for the Tesla Wall Connector. I thought the Wall Connector had an integrated GFCI and Tesla says not to use a GFCI breaker?

I honestly do not want to pay the $650+ for an electrician to come out, run a new 4/3 ROMEX to replace the 6/3 ROMEX should I choose to go with a 60a breaker instead of using the existing 50a breaker and 6/3 wiring, and on top of that use a GFCI breaker costing me even more.

Can I really not use the existing outlet? I guess I could replace the outlet with the Wall Charger itself and use the existing wiring, but then I don't have a place to mount the Wall Charger without leaving the hole where the outlet is now. It's in the wall using a remodel box.

Do you mean like this? I had my electrician install a 14-50 To use the supplied travel charger for my short lived Leaf. When I got the Tesla I asked if he would come and install the Tesla wall charger. He said why bother? Just add an appliance cord. Leave the 14-50 there in case you get a different car.

It took a little Dremel surgery but I got a good result. He approved. In addition to being a certified electrician he is also a certified inspector. I think he knows what he is doing.

 

[dhrivnak]

Yes that is what I have done for over 12 years now, except I purchased a second moble connector and leave it plugged in. Teh reality is 32 amps always has me full in the morning. A good low cost and flexible option.

 

[Ital]

Does the 2023 Model 3 RWD even support more than 32AMP charging?
I am pretty sure in the menu that is the max I am able to select.

 

[E90alex]

Does the 2023 Model 3 RWD even support more than 32AMP charging?
I am pretty sure in the menu that is the max I am able to select.

Yes Model 3 RWD caps out at 32A

 

[JssonB]

Yes that is what I have done for over 12 years now, except I purchased a second moble connector and leave it plugged in. Teh reality is 32 amps always has me full in the morning. A good low cost and flexible option.

32amps has both of mine charged up overnight using a Neo Charge.

 

[Ital]

32amps has both of mine charged up overnight using a Neo Charge.
View attachment 915536

I like it... did not know that existed. Thanks for sharing

 

[random155]

I've been contacting a few local electricians who specialize in installing the Tesla Wall Connector and one told me that I cannot use a NEMA 14-50 plug with it because Tesla didn't design it to work that way. I have an existing NEMA 14-50 that a current third party charger is using. The existing 50a breaker is not a GFCI breaker. This electric company told me I would need to replace it with a GFCI for the Tesla Wall Connector. I thought the Wall Connector had an integrated GFCI and Tesla says not to use a GFCI breaker?

I honestly do not want to pay the $650+ for an electrician to come out, run a new 4/3 ROMEX to replace the 6/3 ROMEX should I choose to go with a 60a breaker instead of using the existing 50a breaker and 6/3 wiring, and on top of that use a GFCI breaker costing me even more.

Can I really not use the existing outlet? I guess I could replace the outlet with the Wall Charger itself and use the existing wiring, but then I don't have a place to mount the Wall Charger without leaving the hole where the outlet is now. It's in the wall using a remodel box.

I used a homemade pigtail for years with a wall charger. I only recently hardwired because now I use the outlet for a garage heater. Now my wall charger is hardwired. The electrician is in it for the money, its business.

 

[comanchepilot]

Yes that is what I have done for over 12 years now, except I purchased a second moble connector and leave it plugged in. Teh reality is 32 amps always has me full in the morning. A good low cost and flexible option.

This is what we did for hte second EV. My wife's Model S uses the wall connector on that side of the garage and my model 3 uses the 50 amp circuit plugged into the Mobile connector which will only accept 32A. I use a properly mounted [inside a sleeve] 50A extension cord to reach the other side of the garage.

 

[hiker007]

Do you mean like this? I had my electrician install a 14-50 To use the supplied travel charger for my short lived Leaf. When I got the Tesla I asked if he would come and install the Tesla wall charger. He said why bother? Just add an appliance cord. Leave the 14-50 there in case you get a different car.

It took a little Dremel surgery but I got a good result. He approved. In addition to being a certified electrician he is also a certified inspector. I think he knows what he is doing.

View attachment 842950View attachment 842951

Is this plugging the Wall Connector into NEMA14-50? But does it defeat the purpose of having hardwired connection for the WC?
I also don't feel comfortable to pigtail/splice 6 AWG wires like this:

 

[JssonB]

Is this plugging the Wall Connector into NEMA14-50? But does it defeat the purpose of having hardwired connection for the WC?
I also don't feel comfortable to pigtail/splice 6 AWG wires like this:

No, he's connecting two wires with a wire nut.
You can wire a pigtail connector into the terminals of the WC and plug it into a 14-50. But I would recommend hard wiring the WC.

 

[stopcrazypp]

Is this plugging the Wall Connector into NEMA14-50? But does it defeat the purpose of having hardwired connection for the WC?
I also don't feel comfortable to pigtail/splice 6 AWG wires like this:

The video linked only shows pre-twisting wires and using a wirenut to connect them (which is a common way to join two wires), it has nothing to do with plugging a wall connector into NEMA 14-50. As people show up thread, typically the way people add a 14-50 to a wall connector is to buy a premade pigtail with a 14-50 connector and then directly screw the conductors into the wall connector (just like how you would install a hardwire). There is no wirenut involved (other than perhaps to cap off the unused neutral wire).