Install a 40 or 50 amp line for NEMA 14-50 outlet?

[FlasherZ]

It depends upon the complexity of the install -- placement, obstacles to work around, etc. Get advice and quotes from 2-3 electricians who can see your environment. I'm going to offer a rough, round $1,000-$1,500 for the complete install including HPWC but that's without knowing a lot of variables.

As for the Powerwall install, there are several different approaches you can use. I'm not familiar enough with the various inverters that will work with it, but that is one way to do it.

As far as setting both cars to charge at different times, some inspectors will allow it, and others won't. Your electrician will help you with the permit/inspection process and perhaps clear it ahead of time with the inspector - and for the work you're doing most locations in the US will require permit/inspection. If the window for charging both is that tight, they may not allow you to do that.

Good luck!

 

[K-MTG]

Thanks you for answering my questions!

 

[LobosPac]

RE: Cost. I installed both a 10-30 and 14-50 for around $1k in SF (not including permit). But it was a very short run (2 feet). And I assume I'll get a 30% tax credit too.

 

[K-MTG]

RE: Cost. I installed both a 10-30 and 14-50 for around $1k in SF (not including permit). But it was a very short run (2 feet). And I assume I'll get a 30% tax credit too.

I thought the tax credit required a dedicate EVSE not an outlet?

 

[LobosPac]

I thought the tax credit required a dedicate EVSE not an outlet?

I'm not a tax accountant, but I do not think it needs to be dedicated. This is from the 8911 instructions:

Qualified Alternative Fuel Vehicle Refueling Property
Qualified alternative fuel vehicle refueling property is any property (other than a building or its structural components) used for either of the following.
- To store or dispense an alternative fuel (defined below) other than electricity into the fuel tank of a motor vehicle propelled by the fuel, but only if the storage or dispensing is at the point where the fuel is delivered into that tank.
- To recharge an electric vehicle, but only if the recharging property is located at the point where the vehicle is recharged.

In addition, the following requirements must be met to qualify for the credit.
- You placed the refueling property in service during your tax year. The original use of the property began with you.
- The property is not used predominantly outside the United States. If the property is not business/investment use property, the property must be installed on property used as your main home

 

[Darryl]

You are looking at it from the perspective whether you have physical room to have a 50/100 amp circuit breaker installed. This is not the issue. You need to be looking of it from the perspective is a 200amp service sufficient to handle your existing load and additionally the 48/72 amp draw for your car. 200 amp seems like a really small service for a house your size. I have 600 amp service (9,000 sq foot under roof) main service and many of my appliances use gas (two tankless gas hot water heaters, gas dryer, gas range, etc ). Many of today's electric meters have the capability to show you what your actual load is. So you could turns on the maximum number of appliances which would be on at any one time and then add in your car requirements and see if you have any headroom. Don't forget your car will have a constant load for longer than any other appliance in your house. This is an area you want to be careful with Mis-calculation can mean burning down your house. My recommendation you have a master electrician come out and explain to him what you are trying to accomplish. They can quickly put a device on your main service to determine your max load.

When I was adding both a 50 amp and a 100 amp service I did all of the calculation using the information from my meter, calculated the new load and used the latest NEC handbook. Even though I thought I had calculated everything right including max load, size of wire to be used, distance from panels etc. I still hired a master electrician to come out and re-calculate everything just to be sure. I ordered all of the materials ( copper wire, square-d breakers, emergency shutoff and conduit) and then had the electrician handle the install. My county requires an emergency shutoff any device/outlet above 60 amps.

 

[K-MTG]

900 AMPS, wow!! I am having my install done without a permit tomorrow on my 200 AMP breaker (5,000 square feet).

 

[ernies]

...and if you do your own install...if you have a problem you will be looking at insurance cancelation. Electrical without a permit is not advisable. Insurance companies do "cause and origin" investigations. They will ask who did the work and where is the permit. Not my idea of a fun way to save a few hundred or even a thousand dollars.

 

[pvogel]

900 AMPS, wow!! I am having my install done without a permit tomorrow on my 200 AMP breaker (5,000 square feet).

I would NEVER consider a high current device install like this without a permit and inspection. Insurance will leave you holding the bag if there is a fire that can be even vaguely blamed on the electrical...

 

[K-MTG]

I would NEVER consider a high current device install like this without a permit and inspection. Insurance will leave you holding the bag if there is a fire that can be even vaguely blamed on the electrical...

Can I get a permit now? After the install?

 

[pvogel]

Not sure. Just went through this with my sister, she needed an EVSE installed but had had a bunch of other electrical work done without permit or inspection. My advice to her was to permit everything as though it was just about to be done and get everything kocher during the inspection for the EVSE. Her electrician was willing to do it that way since he'd done the I permitted work.

 

[DuplexDianne]

Haven't seen this question raised yet....can I just use my existing dryer connection in my laundry room to charge the car? The mobile adapter that's included should be long enough to reach if the car is backed into the garage.

Not sure how thick the cable is, but we have closed the door while charging the kids' 12v Viper with an extension cord...
Is the cable much thicker?

 

[FlatSix911]

Haven't seen this question raised yet....can I just use my existing dryer connection in my laundry room to charge the car? The mobile adapter that's included should be long enough to reach if the car is backed into the garage.

Not sure how thick the cable is, but we have closed the door while charging the kids' 12v Viper with an extension cord...
Is the cable much thicker?

Can you take a photo of your dryer plug?

 

[TexasEV]

Haven't seen this question raised yet....can I just use my existing dryer connection in my laundry room to charge the car? The mobile adapter that's included should be long enough to reach if the car is backed into the garage.

Not sure how thick the cable is, but we have closed the door while charging the kids' 12v Viper with an extension cord...
Is the cable much thicker?

In an emergency yes, but two reasons why this is not a good idea for daily use:
1. You would have to unplug the dryer each time you charge the car and then unplug the UMC.
2. Tesla no longer makes 30A adapters for the UMC, so you would have to use a 14-50 to 14-30 adapter and manually dial down the voltage on the car.

Best to install a 14-50 outlet in your garage if you're going to use the UMC rather than installing a HPWC (now called Wall Connector).

If you're not in the Austin Tesla owners Google group, email me efudman at gmail.

 

[FlatSix911]

You don't need to install a new 14-50 outlet. You can just mod your UMC plug for the 14-30 receptacle as recommended below. You wont melt the adapter if you forget, you'll only trip the breaker. Keep in mind the Model S remembers your amp setting by location, so you only have to remember to set it once.

You can literally just cut the neutral prong off the 14-50 adapter, then it will work in 3 outlet types; 14-30, 14-50 and 14-60. The neutral is not used in the UMC, and it's just a dummy pin. Just be sure to set your max current to 24A when using it on a 14-30 or you will trip the breaker. View attachment 110270

I grabbed the pin with vise grip pliers and ripped it out, then just filled the hole with sealant. I use it all the time and it works perfectly.

 

[TexasEV]

You don't need to install a new 14-50 outlet. You can just mod your UMC plug for the 14-30 receptacle as recommended below. You wont melt the adapter if you forget, you'll only trip the breaker. Keep in mind the Model S remembers your amp setting by location, so you only have to remember to set it once.

I don't think this is good advice. The car has been known to forget that setting with firmware updates, and you shouldn't depend on the circuit breaker. Bad things can happen before a circuit breaker trips, otherwise there would be no such thing as an electrical fire.

 

[KJD]

Haven't seen this question raised yet....can I just use my existing dryer connection in my laundry room to charge the car? The mobile adapter that's included should be long enough to reach if the car is backed into the garage.

Not sure how thick the cable is, but we have closed the door while charging the kids' 12v Viper with an extension cord...
Is the cable much thicker?

Lets be honest here. Anyone that can afford a Model X can also afford to install a proper wall charger in the garage. No need to trip over the cord or block the door from closing.
Tesla — Wall Connector with 24' Cable

 

[Aljohn]

Wow.. a lot of stuff here.

Back the original question. 14-50 plug is typically installed on the 50 Amp circuit breaker with the appropriate wiring for the run length. However the max continuous draw on a circuit is 80% of the circuit's trip point. So a 50 Amp rated circuit (wiring an breaker) can charge 40Amps continuous (80% of 50) -- Not 48 Amps. To get to 48Amp, you would need a 60 Amp rated circuit and wiring -- 80% of 60 amps = 48 amps max. Even installing the HPWC on the 50 amp circuit would be limited to 40 Amps continuous charge, not 48 Amps.

BTW -- When setting the charge on the Model X, It will ask what the max current to charge. I set it at 35 Amps on my 50 Amp circuit. I charge over night, so there is not "rush". I don't care whether the X finishes in 5.5 hours or 6 hours. The cost on the off-peak rate is the same.

 

[ssq]

Lets be honest here. Anyone that can afford a Model X can also afford to install a proper wall charger in the garage. No need to trip over the cord or block the door from closing.
Tesla — Wall Connector with 24' Cable

For the X with 48A onboard charger what's the benefit of getting the new HPWC vs. getting a NEMA 14-50 done for $350. Please help me understand. thanks!

 

[KJD]

For the X with 48A onboard charger what's the benefit of getting the new HPWC vs. getting a NEMA 14-50 done for $350. Please help me understand. thanks!

There is nothing wrong with that at all, as long as the 14-50 outlet is in the parking area.

What I am opposed to is using the dryer outlet in the laundry room that is behind the dryer and behind a closed door. (post #32) Unplugging the dryer (fingers on the prongs) and leaving the door open to the laundry while the car charges is just not a good idea long term.