Building a new home (wall connector/electrical advice)

[AlmightyDollar]

Hello! I will be purchasing a 2021 model 3 LR in a couple of months and am also moving into a new house at the end of April and am hoping someone can help me out.

I plan on purchasing a wall connector to hook up in my future garage. What can I tell the people building my home to make the wall connector setup a breeze once I move in? I currently dont have much electrical knowledge but decided I would want the dedicated wall connector versus the 14-50 NEMA adapter on my mobile charger.

if there are any electrical savvy people here, I would greatly appreciate any advice! I dont plan on buying the wall connector yet but perhaps they can run the appropriate wires for now?

Thanks!

 

[Akikiki]

Home Charging Wiring Guide – TeslaTap

Tesla Model 3/Y Home Charging Guide – TeslaTap

 

[Gauss Guzzler]

Aki's links will tell you everything you need to know.
I'd paraphrase with the following:
A 60A circuit or two would be great. Even 30A is ample. Your main breaker panel will have limited capacity so for example, you might prefer 50A + 30A circuits over a single 60A if it's not easy to get 2 60A circuits in your panel. The wall connector will run on any of them.

Make sure the main panel is "solar ready" as this costs nothing.

If you're considering solar and possibly considering batteries (e.g. Powerwall), consider a "powerwall ready" setup which would require the ability to insert the "gateway" between your power meter and main panel at the very least. A more refined Powerwall setup would have two main breaker panels, one for backup/evening loads and one for grid/daytime loads. This is rather cheap and easy to do now but not so cheap/easy later.

 

[Akikiki]

Ya know, come to think of it. I'd look at SPAN too.

 

[AlmightyDollar]

Thank you guys so much. The links above provided for a much needed read.

 

[joebruin77]

One other suggestion for you. Keep in mind that although Tesla Wall Connectors are reliable, they do have problems now and then. I had a problem with my Gen 2 Wall Connector. Tesla did eventually send me a replacement unit under warranty. But by the time Tesla replied to my warranty inquiry, sent me the replacement unit, and my electrician installed it, 4 or 5 weeks went by. During this time without my Wall Connector, I made do by charging at local level 2 chargers. But it was time consuming and inconvenient. So in addition to installing the replacement Wall Connector, I also had my electrician install a 14-50 outlet. That way, if I ever have a problem with my Wall Connector again, I can temporarily rely on the 14-50 outlet for charging until I can get the Wall Connector repaired or replaced.

Since you are building a new home, I would have wiring installed to have BOTH a Wall Connector and a 14-50 outlet.

 

[Akikiki]

I like this idea. Seems like it provides a backup method to check the circuit and still charge the car. However, there may be an issue with local code. I suggested this idea a couple of years ago here. And someone far more knowledgeable than I pointed out that code does not permit two uses or potentially uses of the same circuit that would overload the circuit.

As I recall, its okay to have both provided each is on its own circuit, but not allowed is two sources on the same circuit. Not a hardwired WC connection and a 14-50 outlet together. I can't prove or verify it. Can someone smart on these things speak up, please?

 

[Gauss Guzzler]

Yes and no.

Generally you need a dedicated wire and breaker for each high power device (anything other than a standard 110V / 15A outlet or light).

However, the total combined amperage of all the breakers in a panel (or subpanel) can greatly exceed that of the breaker feeding it. So you could for example have a single 60A breaker and single run of 6 AWG wire feeding a subpanel in your garage containing multiple 60A, 50A etc. breakers branched out to multiple outlets or wall chargers. Many wall chargers can even be configured to automatically coordinate with each other so as not to overload the circuit when used simultaneously.

This obviously isn't the preferred way to do it, but it can be done if needed. And it could be retrofitted later too. You could replace the wall charger with a subpanel that then feeds a wall charger and a 14-50 outlet.

 

[joebruin77]

Great question. Unfortunately I do not know the exact answer. I did have a licensed electrician install the whole setup and that included a subpanel.

 

[NickFie]

I suggest asking the electrician to install and connect with copper cable a 100 Amp subpanel in the garage.

After that, everything is easy. Easy to install, easy to expand, easy to modify/ upgrade. Second EV connection? No sweat! Your own welding equipment? Sure! You’ve taken up sculpture and need an industrial-grade compressor to power the chisel? Covered!

Also, the panel, if it’s visible, serves as a disconnect for your chargers.

There’s some chance Tesla or other EV vendors will introduce higher power home charging options as battery capacity edges past 100 KWh. CyberTruck, Plaid+, Rivian...

Old-timers remember dual-charger S 85s that could use 80 Amps at 245 Volts.

 

[Rocky_H]

There’s some chance Tesla or other EV vendors will introduce higher power home charging options as battery capacity edges past 100 KWh. CyberTruck, Plaid+, Rivian...

Old-timers remember dual-charger S 85s that could use 80 Amps at 245 Volts.

Very little chance.
Tesla has been moving toward lower power, not higher power.
Used to be max 80A
Then 72
Then 48
And then they replaced their wall connectors with 48A being the max it can provide.
They have shown this ongoing trend of going lower and lower with the onboard chargers and the external charging devices, and that's the way it is. And any higher power charging that anyone wants should be from Superchargers.

 

[Akikiki]

Ya know, @Rocky_H is right about this. Tesla has been moving away/lowering the charging for non DC charging. Interesting observation when you think about it. And why have the customers not been complaining? Hmmm.

I would guess that when we need to charge at home, and we plug in to charge, most of us plug in and walk away and we don't go back to drive for 6-7 hours. So it would make little difference, most of the time, how long it takes to charge as long as its charged when we are ready to leave in the morning be it 05:00 or 07:00. If it means charging needs to start at 9 pm vice 11 pm, it matters little - again as long as its full to the point we are charging. Well, that's my guess - even if no one was asking. (Trying to find excuses not to work on my taxes.)

 

[davewill]

Since you're building a new home, I would go big. In my opinion, that should be a 60a circuit on each side of the garage ready to wire EVSEs into. In addition I would add at least one 14-50 and one dedicated 120v outlet, located so that a car in either space or even on the driveway could use it with the mobile connector. Take the time to think about how you would park (nose in or out), and sketch things out on paper. Don't plan on using the full length of your EVSE cord on a regular basis as it's a nuisance to coil and uncoil it all the time. You should be able to grab the plug, turn and plug it into the car.

I've been driving electric for 9 years now, and there have been a few occasions where either a broken EVSE or a blocked driveway has caused me to need to use a mobile connector. One time backyard construction caused me to have to park at the end of my driveway and charge using a 120v extension cord (back in LEAF days). Also sometimes my daughter's Prius Plug-in has charged in my driveway while charging two EVs inside the garage.

 

[Akikiki]

@AlmightyDollar, @davewill makes some excellent points and its great advice. If you are building a new home, you have the opportunity to maximizes ev charging for yourself, and a chance to future proof it for the next owner should you choose to sell later. You will be able to say EV Ready in your ads.

There's several threads here on TMC that showcase owners' setup. You should be able to get some good ideas from them. Here's a recent one that was very popular a couple of weeks ago. Let's See Your Charging Setup

 

[miimura]

When I had my house built before I had EVs, I specified a 50A 240V outlet on each side wall of the two car garage. This works well, but in retrospect, I would recommend a 125A sub-panel in the garage. This would allow for some 20A 120V outlets in addition to 50A or 60A EVSE circuits. This is especially true for a detached garage.

 

[Rocky_H]

And why have the customers not been complaining? Hmmm.

And why do you think the customers have not been complaining? Hmmm.

 

[Gasaraki]

Hello! I will be purchasing a 2021 model 3 LR in a couple of months and am also moving into a new house at the end of April and am hoping someone can help me out.

I plan on purchasing a wall connector to hook up in my future garage. What can I tell the people building my home to make the wall connector setup a breeze once I move in? I currently dont have much electrical knowledge but decided I would want the dedicated wall connector versus the 14-50 NEMA adapter on my mobile charger.

if there are any electrical savvy people here, I would greatly appreciate any advice! I dont plan on buying the wall connector yet but perhaps they can run the appropriate wires for now?

Thanks!

Run 4 gauge from your 60A breaker in your panel to the place where you want the wall connector. Have them connect that to a quick disconnect right next to (close to) where you want your wall connector to be.

 

[XLR82XS]

Since you are building a new home, I would have wiring installed to have BOTH a Wall Connector and a 14-50 outlet.

+2. The conduit running down the wall between my garage doors terminates at a 14-50 outlet that I had installed at the recommended height for the wall connector. If I ever decide to get a wall connector - I'm ready. 60-amp circuit BTW.

I don't see the need for wall connector anytime soon since the mobile charger works flawlessly and provides 30mph charge speeds.

 

[freeAgent]

I like @davewill's "go big" approach with new construction. Putting a 100-amp sub-panel in your garage will allow you a lot of flexibility for whatever comes in the future (and save money for incremental changes in your garage wiring down the road). I personally like 14-50 outlets rather than hardwiring in case I need to unplug my EVSE for some reason (such as it breaking). However, if you use a 14-50 plug, you'll be limited to charging at 40 amps. Whether that limitation actually matters to you or not is something worth asking. For most people, the difference between 40 amps and 48 amps is not going to be noticeable, but if you're using a huge amount of battery all the time and won't have 8 solid hours to charge between those trips, it may be preferable. It's not like you're going to get supercharger (72 kW or higher) speeds at home, though, even if you do hardwire the EVSE and go with the full 48 amps on it. A 14-50 receptacle on two dedicated 50 amp circuits on both sides of a garage would be my ideal, personally. That way you could charge two EVs at 40 amps simultaneously like a boss.