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Owners of two teslas and use a wall charger I have a ? for you?

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No ICE

2016 S75D pearl AP1, & 2014 silver S85 AP1
Apr 10, 2016
102
72
Kansas City
We are planning on ordering our tesla 75D within the week. We are also having an electrician come to the house to run power to the garage for the tesla wall connector.
Tesla — Wall Connector with 24' Cable
My question for you owners of more than one tesla is how are you set up at home for charging. Are you using one of these wall connectors for two cars. Did you run two sepparate Nema 14-50 outlets? I am confused by the wall connector sharing feature. I guess as long as I run a larger amp circuit breaker (90 -100 amp) it would allow me to piggy back an extra charging cable off it some how? The tesla website doesn't really explain this well. I can see us owning a model 3 sometime in the next few years so I would like to be as prepared as possible while I am having the electrician out for the intitial setup.
Any advice would be greatly apriaciated.
Thanks all,
John
 
You don't say what service your house has. I would suggest that the electrician set up the garage with a major electrical panel - the same as if it were a whole new house. That way you will be able to deal with the EV future and possibly a solar system as well.
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There is a thread back about the new WC install and the sharing feature. If I remember correctly it knows the total load you can connect and then proportions out the power to each car based on where it is in the charging cycle and when it got plugged in. You can also tweak this a bit by staggering when the cars charge if you know that one car needs precedence over the other on a regular basis. Just set it's charging time earlier.
 
Wall Connectors do not use 14-50 outlets. They are hard wired to the panel. To charge two cars at the same time you need two Wall Connectors that get linked together to control the maximum current that will be drawn from the wall. I second the recommendation to install a sub-panel in your garage.
 
Thanks for the feedback. I have a 200 amp service to my house, however I fear it may be almost tapped out. We finisished our basement a few years ago and have already ran a sub box off of it. The electrician ( over the phone) was already concerned about the possibility of needing to upgrade to 400 amp service which would of orde fix all worries with more $$! I will know more today when he comes out. I hope that's not the case!
 
Two HPWCs is the best setup for two Teslas, although two 14-50s would be plenty for most all needs.

Each HPWC requires its own dedicated circuit breaker and wiring from your panel or a sub-panel. The sharing feature allows the two cars to share a combined max power draw. For instance, if your service has room for an extra 100 amp breaker, either car can use the full amount (80 Amps for continuous load) if the other is not charging. If both are charging the two will share the 80 amps. If your panel cannot support another 100 amp circuit, then the HPWC can be adjusted to share whatever is available.

This can save a bunch of money compared to upgrading your utility service.

GSP
 
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Thanks for the feedback. I have a 200 amp service to my house, however I fear it may be almost tapped out. We finisished our basement a few years ago and have already ran a sub box off of it. The electrician ( over the phone) was already concerned about the possibility of needing to upgrade to 400 amp service which would of orde fix all worries with more $$! I will know more today when he comes out. I hope that's not the case!

HPWCs would likely be the least expensive option then. You may also want to consider changing a water heater or range to gas if that is an option for you.

GSP
 
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Or an example I read a while back. Say your 200a panel has 50a available (40a continuous).

Option 1 - 14-50 outlet

Install one outlet and move the cable between the cars

Option 2 - 2 14-50 outlets.

You can use two cables, but will need to manually manage the power use between the two.

Option 3 - two HPWC

Run a 50a circuit to a subpanel. Put two 50a circuits in the sub, one for each HPWC. Set the HPWC to max of 40 and connect the two with the serial data port.

The HPWC will automatically balance and not use more that 40a.
 
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At our current house, we have an HPWC on a 100A circuit on one side, and a NEMA 14-50 outlet on the other. Works like a charm. In fact, I kind of regret the money I spent on the HPWC (which used to be more expensive) as we have been here over 2 years and never needed the extra capacity.

At our old house, we had two 14-50's on a center post in the garage. That was all we needed for 6 years there with 2 EVs.

In fact for about a year and a half at the old house, just for minor convenience I had moved the Roadster to the third bay of the garage and used a 120V outlet. That was always enough (at least for that car; there were probably a couple of times it wouldn't have been enough for our other car).
 
I've got a dedicated 200A panel in my garage for the EVs with a separate meter with my utility's EV/TOU plan. Off the panel I have two HPWCs with 100A breakers. Most of the time this is overkill, but it guarantees that I can almost charge from near empty to 90% during the TOU window of 4 hours and not have to manually manage charging. Both cars are set to charge at 1am and I'm done. I also have a J1772 charger for our Volt that is wired to a 14-50 that is on our house panel, so if needed I can charge outside of the TOU window without paying for it up the a$$.

Most of the time I could have survived with sharing a single HPWC, but I decided the expense of having two was worth not having to coordinate charging with the other drivers of the house. The rule is: in the garage, plug-in.
 
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