Adding second M3, 1 Dryer Outlet thus far

[JBailey895]

[disclaimer, I'm an electrical idiot]

We bought my wife's LR RWD 3 last year, and she wouldn't share, so I just bought a 3P+. We have used her portable charger connected to our dryer outlet (we have a gas dryer anyway), and its worked fine, she only charges once or twice a week, and disconnects the cable each time. Our garage is about 45' from the main breaker panel, and separated by front entrance and family room, so running a dedicated line for charging didn't seem cost-effective.

Super excited to avoid the pump, but have a charging question. Its a 3 car garage, and her stall is next to the washer/dryer area, and easy access to the dryer outlet. Mine is on the far-side of the garage, but we have a large attic space above the garage, and numerous wires/gas pipes located up there. I'm wondering if I can just tap into the existing dryer line outlet, and use a j-box to add additional line through the attic ceiling to drop down into the garage in an appropriate place for my stall to hang a charger.

We have a 200A breaker panel for our 3k sf home, and all the breaker space is currently occupied, but I've been told some could be combined to add additional circuits.

I know I'll have to hire an electrician to do any of this stuff, but wanted to tap the collective wisdom for advice before I start getting bids, if possible.

Questions:
1. Could we "get by" with this configuration? Ie just extending the one line in attic, and adding another outlet for the second bay;
2. Could only 1 car charge at a time, in any given night?
3. Would Tesla wall chargers benefit us in this application?

Thanks for any suggestions/input.

Joel

 

[ItsNotAboutTheMoney]

2 HPWCs _could_ be used in a primary-secondary set-up, limited to 24A. Depending on your miles, that could be enough.

But if you're going to get an electrician and do any runs, it's an opportunity to assess available power.

 

[Big Dog]

if you are gonna get an electrician I'd upgrade to a 60 amp circuit if your electrical box will support it, even if you ultimately decide to install a NEMA 14-50 outlet. That way you can: 1) charge at 48 amps if you ever need to; 2) install a Tesla WC if you have teh cash and/or 3) install two Wall Chargers one as a Master and one as a Slave so that they can share the same circuit.

btw: dryer plugs are not designed for multiple uses, ie., plug in, plug out. If you go the NEMA 14-50 route, make sure your electrician installs a heavy duty receptacle (~$90), not the $10 version that you can find at Home Depot or Amazon.

fwiw: we have to model 3's and one WC; we only have a 100 amp panel, but installed a sub-panel. Don't charge very often, so just park the car on the other side of the garage so one can charge.

 

[JBailey895]

Thanks for the responses guys, sounds like if we "beefed up" the NEMA 14-50, and just rotated cars for charging purposes, we would be "ok", I was thinking it'd be nice to plug them in each night, but, as I mentioned, wife currently only plugs in once or twice a week, so if we coordinate properly, shouldn't be an issue. She can't get her car into the single stall (only about 2" on either side to play with), so I'll still have to do some car juggling if I don't wire a second charging station.

 

[COrocket]

Thanks for the responses guys, sounds like if we "beefed up" the NEMA 14-50, and just rotated cars for charging purposes, we would be "ok", I was thinking it'd be nice to plug them in each night, but, as I mentioned, wife currently only plugs in once or twice a week, so if we coordinate properly, shouldn't be an issue. She can't get her car into the single stall (only about 2" on either side to play with), so I'll still have to do some car juggling if I don't wire a second charging station.

Be careful “beefing up” to a 14-50 outlet. If you are charging from a 30 amp dryer outlet, most likely the wiring installed in the wall was only installed to supply 30 amps unless the builder had a reason to put thicker (+$) wire in the wall. If I were you, I’d either leave the charging situation as is and rotate the cars out, or install Tesla wall connectors set to share 30A since It’s not code compliant to daisy chain regular 240V outlets.

Another option would just to plug the lower mileage car into a regular old outlet and get 5-7 mph charging which would probably keep your wife’s car charged daily if she’s only plugging into the dryer once a week. It might be slightly less efficient, but that slight difference would take a really long time to offset $1000 worth of wall chargers, plus materials/labor of a professional install.

 

[JBailey895]

"1) charge at 48 amps if you ever need to; 2) install a Tesla WC if you have teh cash and/or 3) install two Wall Chargers one as a Master and one as a Slave so that they can share the same circuit."
Will a wall charger and a 14-50 work on the same circuit, ie leaving the 14-50 and adding a HPWC? If we avoided charging at the same time?

 

[neurocutie]

yeah sounds like the wifey could get by with a standard 120VAC 12A outlet for charging, while you use the dryer outlet. For minimal cost, you could use an extension cable for the dryer outlet if she insists on staying close to the laundry room. Unless you *want* to spend >> $60 (cost of extension cord for 30A)... don't keep plugging/unplugging from either dryer outlet or extension cord though...

 

[woodguyatl]

"1) charge at 48 amps if you ever need to; 2) install a Tesla WC if you have teh cash and/or 3) install two Wall Chargers one as a Master and one as a Slave so that they can share the same circuit."
Will a wall charger and a 14-50 work on the same circuit, ie leaving the 14-50 and adding a HPWC? If we avoided charging at the same time?

They will work BUT don’t do it. It is dangerous and a code violation. Two HPWC’s would be the way to go. They will communicate with each other to be sure to that they never draw more current than the circuit is designed for.

 

[IROAR]

2 wall chargers with communication line between them enables load management.The 2 model 3s can be plugged in without concern for blowing the circuit. Ideal would be a 60amp circuit if panel and budget permit.

 

[JBailey895]

I just measured, if I move the outlet, I can reach both cars with the mobile connector, if the current circuit is only charging at 24A, is there any benefit in installing a HPWC if I don't upgrade the circuit?

 

[JBailey895]

Just as a follow-up, I went ahead and installed a 14-50, tapping into a 50A circuit I had feeding my steam shower, and found out later I am limited to the Mobile charger's 32A limits. I "could" get 40A with the HPWC, but I'm already meeting my goal of overnight charging for the LR or P cars, so I guess I'm good. Thanks for the input!

 

[Tummy]

You might consider a dryer buddy that will switch from one to the other.
Products

 

[Electric700]

... install Tesla wall connectors set to share 30A since It’s not code compliant to daisy chain regular 240V outlets...

Yes, when configured, the Tesla Wall Connectors can allow you to share the available power for two cars. This might be a more convenient option to look at later on.

 

[JBailey895]

Thanks all, with the relocation of the 14-50, I can reach both cars with their mobile chargers, and that seems to be the solution for now. 32A charging starting at 11 pm has been sufficient to "top off" each car thus far, so I'm a happy camper.

 

[davewill]

Just as a follow-up, I went ahead and installed a 14-50, tapping into a 50A circuit I had feeding my steam shower, and found out later I am limited to the Mobile charger's 32A limits. I "could" get 40A with the HPWC, but I'm already meeting my goal of overnight charging for the LR or P cars, so I guess I'm good. Thanks for the input!

If the steam shower is still attached, then the install doesn't meet code.

 

[anhdinhnguyen@]

Testing ... It seems I can not post anything. This website not allow me to post????

 

[jjrandorin]

Testing ... It seems I can not post anything. This website not allow me to post????

You can post just fine, however posts that appear to be advertising are removed by moderators as advertising requires being a vendor here.