New Home Build - Wall Connector - NEMA 14-50

[ccathcart609]

Hey All!

So my current home setup is a sub panel in my garage. And a wall charger hardwired to it.

New home build. Builder installed the sub panel in garage. Around the corner installed a 240v 50A access plus a NEMA 14-50 outlet.

Question is, does the NEMA give me any advantage? Should I not have to hard wire the wall charger at new house and just use the NeMA? Am I getting same performance? From what I read it drops to 32A. Is that right? Thanks!

 

[brkaus]

A 14-50 with the Tesla portable connector will charge at a max of 32a.

If you put in a WC and a properly wired circuit, you can charge at 48a (assuming you don’t have a car with a lower rate like a RWD model).

 

[Watts_Up]

When using a NEMA 14-50 outlet you need to have a GFCI circuit breaker, which is quite expensive,
so people in this forum recommend to install a Wallcharger instead.

 

[beatle]

A receptacle gives you the ability to take your UMC with you when you travel. If you buy a gen1 UMC you can charge at 40A. You can easily and quickly replace the connector yourself if it fails. You can also connect an extension cord to the 14-50 and charge further away if necessary. I did this in a pinch when I had my Lightning, and when I was working on my other car in the garage bay normally occupied by the Tesla.

That said, IMO these benefits don't outweigh the costs of the GFCI for the 14-50, higher potential charge speeds of a HPWC (if the wiring supports a 60A circuit) and the ability to install a second HPWC and link them. I have my gen1 UMC mounted to a bracket so it looks nicer, and it takes the strain off the plug, but a HPWC looks nicer still.

 

[Eric33432]

A receptacle gives you the ability to take your UMC with you when you travel. If you buy a gen1 UMC you can charge at 40A. You can easily and quickly replace the connector yourself if it fails. You can also connect an extension cord to the 14-50 and charge further away if necessary. I did this in a pinch when I had my Lightning, and when I was working on my other car in the garage bay normally occupied by the Tesla.

That said, IMO these benefits don't outweigh the costs of the GFCI for the 14-50, higher potential charge speeds of a HPWC (if the wiring supports a 60A circuit) and the ability to install a second HPWC and link them. I have my gen1 UMC mounted to a bracket so it looks nicer, and it takes the strain off the plug, but a HPWC looks nicer still.

According to the OP, the 14-50 has already been installed. Either builder installed a GFCI breaker, or he did not, but presumably since it is a new house it has been inspected and is OK. If the builder did not install a GFCI breaker, if you are concerned about safety you can ask builder to install a GFCI, or install one yourself, but unless your area is one that does not require GFCI for 240 volt receptacles in the garage I would be surprised if this was allowed to be installed without a GFCI by your local inspector. There are also plenty of 14-50's installed before the code required one that do not have GFCI breakers with very little problems, but the code now requires it due to a few freak accidents over the years.

Since the builder already installed the 14-50, I would leave it alone, and since he installed a 100 amp sub panel in the garage, I would just install a new circuit with a Tesla Wall Connector. You can install a 60 amp breaker and a Tesla Wall Connector which will give you 48 amp charging unless you have the M3 RWD, which maxes out at 32 amps.

If you are going to regularly use the 14-50 I would check to ensure it is not a cheap Leviton receptacle, which have a history of overheating. If a Leviton I would replace it with a Hubble.

 

[davewill]

If you're using a wall connector on that circuit, you should hardwire it. Some people have used 14-50 pigtails on their wall connectors, but it's contrary to the install instructions.

There's a couple of ways a hardwire install can be done:

1. Turn off the circuit breaker. Remove the 14-50 outlet. Mount the wall connector over the existing box. If there's enough slack in the wiring, you can hook up the wall connector to the existing wires. If there isn't, and there probably won't be, then you can use the box as a junction point and extend the wiring to do the hookup.

2. Turn off the circuit breaker. Remove the 14-50 outlet and replace the faceplate with one that can accept a conduit connection. Use a flexible conduit pigtail , or run THHN wiring in hard conduit between the box and where you want to mount the wall connector. If you want to get fancy, you can open the wall and run wire from the box to your wall connector install location behind the drywall, but I wouldn't bother.

Either way, configure the wall connector for a 50a circuit, which will net you 40a charging. Some folks will make a fuss about the circuit possibly having a GFCI breaker, and urge you to change it to non-GFCI. It is not necessary to change it. You should be absolutely fine.

There's a slight chance the builder installed a 40a circuit (check the breaker), in which case, you'll have to configure the wall connector for 32a charging.

If you discover that the builder used wiring suitable for a 60a circuit, you could consider changing the breaker and running the wall connector at a full 48a, but they likely used 6/3 Romex, which can't be used for 60a.

 

[Eric33432]

If you're using a wall connector on that circuit, you should hardwire it. Some people have used 14-50 pigtails on their wall connectors, but it's contrary to the install instructions.

There's a couple of ways a hardwire install can be done:

1. Turn off the circuit breaker. Remove the 14-50 outlet. Mount the wall connector over the existing box. If there's enough slack in the wiring, you can hook up the wall connector to the existing wires. If there isn't, and there probably won't be, they you can use the box as a junction point and extend the wiring to do the hookup.

2. Turn off the circuit breaker. Remove the 14-50 outlet and replace the faceplate with one that can accept a conduit connection. Use a flexible conduit pigtail , or run THHN wiring in hard conduit between the box and where you want to mount the wall connector. If you want to get fancy, you can open the wall and run wire from the box to your wall connector install location behind the drywall, but I wouldn't bother.

Either way, configure the wall connector for a 50a circuit, which will net you 40a charging. Some folks will make a fuss about the circuit possibly having a GFCI breaker, and urge you to change it to non-GFCI. It is not necessary to change it. You should be absolutely fine.

There's a slight chance the builder installed a 40a circuit (check the breaker), in which case, you'll have to configure the wall connector for 32a charging.

If you discover that the builder used wiring suitable for a 60a circuit, you could consider changing the breaker and running the wall connector at a full 48a, but they likely used 6/3 Romex, which can't be used for 60a.

Great info for OP. Definitely do not want to use the 14-50 for the TWC.

Or just leave the original 14-50 and install a new circuit for a hard-wired TWC since builder installed 100 amp sub panel in the garage.