Charging [at home] question [can I use a 100 foot extension cord to a 14-30?]

[Big Dog]

I'd go with either a 6-50 or 10-30 outlet. Either one eliminates the need to run a neutral wire, so you only need to run 3 wires instead of 4. The cost of the wire is one of the major expenses of running to an outlet 100 feet away from the circuit breaker.

The marginal cost of wire is relative chump change in comparison to California labor costs to install either.

 

[Big Earl]

Like Greg said, 10-30 is the cheapest solution and provides the same charging performance as 14-30. This will easily provide an overnight charge. A typical charge might be 20-80% or 30-90% every few days or about 50kWh (60% of the 82kWh battery).

The standard 80% limit on a 30A outlet gives you 24A at 240V for 5.7kW. So to add 50kWh at 5,7kW would take about 8.7 hours. So if you're good with a 8.7 hour charge every 150-190 miles and can put in a 30A outlet you'll be fine.

I'd go with either a 6-50 or 10-30 outlet. Either one eliminates the need to run a neutral wire, so you only need to run 3 wires instead of 4. The cost of the wire is one of the major expenses of running to an outlet 100 feet away from the circuit breaker.

The NEMA 10-series eliminates the ground, not the neutral. It is obsolete and should not be used for new installations. If you want to eliminate the neutral, install a NEMA 6-series receptacle.

 

[bjrosen]

Don't cheap out on the installation, put in a 60A line and have it hardwired. The bulk of the cost is just having the electrician show up at your house, the difference in cost between a 40A line and a 60A line is chump change. That wire is going to be there for at least the next 50 years, the EVSE or whatever comes after EVSEs will change every 10 years or so but the copper wire won't.

 

[Gauss Guzzler]

The NEMA 10-series eliminates the ground, not the neutral. It is obsolete and should not be used for new installations. If you want to eliminate the neutral, install a NEMA 6-series receptacle.

Unfortunately Tesla doesn't offer a 6-30 adapter so the OP would either have to use an aftermarket adapter or upsize the wiring to 40A in order to legally use a 6-50 outlet. But you're right, the lack of ground isn't great, might limit future EV charger support, and such a circuit should really be installed with a more expensive GFCI breaker - at which point it'd be a lot smarter to just use slightly larger wiring with a regular outlet and breaker instead.

So I'll revise my "cheapest option" recommendation to be 2-conductor AWG8 on a 40A breaker with a 6-50 outlet. Often the cheapest option is to drag romex thru the attic but if your run is going to be in conduit anyway you could use a 50A breaker instead.

bj offers wise advice to look to the future. Consider higher current if you think you might do major commuting and/or get a less efficient vehicle like a truck or van. And/or consider a 2nd outlet as you'll likely never own another gas car. Lastly, consider 3-conductor wiring if you think you might use it for an RV or convert it to a sub-panel someday.

 

[kennyfreemoney]

I run a 25' 10-30 extension cord from my dryer outlet to my mobile charger. works just fine. I charge every night. I'm currently in a rental for a few more months. Otherwise I would either install a Tesla Wall Charger, or a 14-50 plug

 

[wws]

The NEMA 10-series eliminates the ground, not the neutral. It is obsolete and should not be used for new installations. If you want to eliminate the neutral, install a NEMA 6-series receptacle.

The only time an electrician would install a 10-30 is when repairing an existing, but broken, 10-30 receptacle. Any new "30 amp" installation must use a 6-30 or 14-30 - depending on whether neutral is needed or not. EVs charging at 240V don't need a neutral, so technically a 6-30 is all that is needed. While Tesla doesn't offer a 6-30 adapter, and IMHO they really should, evseadapters does: NEMA 6-30 Adapter for Tesla Model S/X/3/Y Gen 2 – EVSE Adapters

 

[GregD60]

The marginal cost of wire is relative chump change in comparison to California labor costs to install either.

6 gauge THHN wire at Lowes runs $1.16 per foot, so $116 for a 100 foot run plus sales tax.

 

[GregD60]

Unfortunately Tesla doesn't offer a 6-30 adapter so the OP would either have to use an aftermarket adapter or upsize the wiring to 40A in order to legally use a 6-50 outlet. But you're right, the lack of ground isn't great, might limit future EV charger support, and such a circuit should really be installed with a more expensive GFCI breaker - at which point it'd be a lot smarter to just use slightly larger wiring with a regular outlet and breaker instead.

So I'll revise my "cheapest option" recommendation to be 2-conductor AWG8 on a 40A breaker with a 6-50 outlet. Often the cheapest option is to drag romex thru the attic but if your run is going to be in conduit anyway you could use a 50A breaker instead.

bj offers wise advice to look to the future. Consider higher current if you think you might do major commuting and/or get a less efficient vehicle like a truck or van. And/or consider a 2nd outlet as you'll likely never own another gas car. Lastly, consider 3-conductor wiring if you think you might use it for an RV or convert it to a sub-panel someday.

From a futures standpoint, it would be nice to run AWG6 wire to support a Tesla wall connector in the future. It sounded like the OP wanted to keep the initial cost down however. Also, the wall connector only needs 3 conductors not 4.

Regarding ground versus neutral, I was conflating 10-30 and 6-50. Thanks Big Earl and others for the correction.

 

[M3BlueGeorgia]

I'd go with either a 6-50 or 10-30 outlet. Either one eliminates the need to run a neutral wire, so you only need to run 3 wires instead of 4. The cost of the wire is one of the major expenses of running to an outlet 100 feet away from the circuit breaker.

BTW. 10-30 hasn't been code since 1997. It doesn't have a ground, so shouldn't be used for car charging.

6-50 is a good solution.

 

[Candleflame]

100 feet should be ok but you have to dial down the charge rate. 16a/240v will get way too hot. 8 to 10 amps should be ok.