Need advice on how best to charge vehicles at home.

[jk0291]

I'm moving from an apartment which has a designated charging spot to a house with a single car attached garage (I will only have one space for charging at a time). Currently have a model Y (call it A) which will be used the most on my daily commute. I'll buy a second EV that is not a tesla (Call it B) for my wife who will only be using this thing a couple miles a week.
I'm torn on how I should set up charging.
1. Get Nema 1450 installed and use my mobile charger to charge A and charge B once or twice a week in the garage with a tesla to J1772 adaptor.
2. Get Tesla wall charger installed to charge A and charge B once or twice a week with a tesla to J1772 adaptor.
3. Get generic EV charger and use J1772 adaptor to tesla adaptor (allowing for potentially switching out tesla for a different EV in the future)

How reliable are these methods of conversion, and how bad would it be on B (Likely to be Chevy bolt EV)'s battery to charge only twice a week and never really go below 70% probably with its low usage?
Is the wall charger worth it for me if I'm using my tesla for at the very least 4 more years?
how would you personally handle this scenario?

Thank you.

 

[Cosmacelf]

I would get a J1772 charger, not a Tesla one. The adapter to a Tesla from a J1772 is a lot more robust and reliable than the other way. Also if you’re getting a 14-50 installed, why not install another 240V receptacle. Even a 20A 240V receptacle connected to a J1772 charger would work well for the B car.

 

[Silicon Desert]

Have you used the forum search feature? There are LOTS of threads on here already about this topic. Maybe too many threads

 

[jjrandorin]

I'm moving from an apartment which has a designated charging spot to a house with a single car attached garage (I will only have one space for charging at a time). Currently have a model Y (call it A) which will be used the most on my daily commute. I'll buy a second EV that is not a tesla (Call it B) for my wife who will only be using this thing a couple miles a week.
I'm torn on how I should set up charging.
1. Get Nema 1450 installed and use my mobile charger to charge A and charge B once or twice a week in the garage with a tesla to J1772 adaptor.
2. Get Tesla wall charger installed to charge A and charge B once or twice a week with a tesla to J1772 adaptor.
3. Get generic EV charger and use J1772 adaptor to tesla adaptor (allowing for potentially switching out tesla for a different EV in the future)

How reliable are these methods of conversion, and how bad would it be on B (Likely to be Chevy bolt EV)'s battery to charge only twice a week and never really go below 70% probably with its low usage?
Is the wall charger worth it for me if I'm using my tesla for at the very least 4 more years?
how would you personally handle this scenario?

Thank you.

In that instance, I would probably:

1. Determine capacity for charging in totality

2. Have a non tesla specific wall connector installed that is weather resistant, so that it would reach both the parking spot in the garage and the one in front of the garage (mounted on the outside of the garage.

3. get a NEMA 240V outlet installed in the garage (on a separate circuit).

If, for example, I could put one 50amp circuit in from a capacity standpoint, I would probably have one 30 amp circuit installed and put on the wall connector, and one 20 amp circuit installed as an outlet.

having the flexibility to plug both things in if desired would beat out the faster charging speed of only having one, for me.

 

[strider]

My reco is a variation on @jjrandorin. You could install 2 x 14-50's on the same circuit and plug in each respective mobile charger. Then just use the charger for the respective vehicle that is in the garage.

This is what we did when we lived in a house w/ a single car garage and had the Roadster and Model S and it worked great.

No issues w/ low utilization on the Bolt. The least amount of battery calendar degradation happens at 50% SOC.

 

[jk0291]

I would get a J1772 charger, not a Tesla one. The adapter to a Tesla from a J1772 is a lot more robust and reliable than the other way. Also if you’re getting a 14-50 installed, why not install another 240V receptacle. Even a 20A 240V receptacle connected to a J1772 charger would work well for the B car.

Do you mean twinning? I briefly spoke to the electrician who said if he makes two 14-50, he won't twin them as it's not recommended, instead he would charge for two separate ones ($400-500 each)

 

[jk0291]

My reco is a variation on @jjrandorin. You could install 2 x 14-50's on the same circuit and plug in each respective mobile charger. Then just use the charger for the respective vehicle that is in the garage.

This is what we did when we lived in a house w/ a single car garage and had the Roadster and Model S and it worked great.

No issues w/ low utilization on the Bolt. The least amount of battery calendar degradation happens at 50% SOC.

Nice! Do you mean twinning? My electrician said no to twinning for some reason. I'm new to this homeowner stuff.

 

[jjrandorin]

My reco is a variation on @jjrandorin. You could install 2 x 14-50's on the same circuit and plug in each respective mobile charger. Then just use the charger for the respective vehicle that is in the garage.

This is what we did when we lived in a house w/ a single car garage and had the Roadster and Model S and it worked great.

No issues w/ low utilization on the Bolt. The least amount of battery calendar degradation happens at 50% SOC.

Code says you cant do that (two EV charging outlets on the same circuit) unless you can physically lock one of them out in some manner that isnt "I will just unplug it".

You can do two wall connectors that are able to load share, if one wanted, and be code compliant, but you cant put two outlets on the same circuit for ev charging without having a device that physically only lets one circuit operate at a time. Thats why I would never recommend anyone install 2 outlets for charging on the same circuit (and why the OPs electrician is correctly telling them no to that).

 

[Cosmacelf]

Do you mean twinning? I briefly spoke to the electrician who said if he makes two 14-50, he won't twin them as it's not recommended, instead he would charge for two separate ones ($400-500 each)

No, not twinning, that's actually against electrical code, so your electrician was right. I would spend the money and do it right and get two outlets installed in locations that make sense. Alternatively, since car B won't be driven much, you could charge it via a 120V plug. If it is a 20A receptacle, so much the better. But even a 15A receptacle will work for an occasional use car.

BTW, at least for a Tesla wall connector, it is recommended to directly hard wire it rather than get a NEMA 14-50 receptacle.

 

[CKwik240]

Alternatively, since car B won't be driven much, you could charge it via a 120V plug. If it is a 20A receptacle, so much the better. But even a 15A receptacle will work for an occasional use car.

Can other EVs make use of a 20A 120V receptacle?

 

[strider]

Why are 2 outlets on the same circuit not ok? I have multiple 5-15 outlets on the same 20A breaker. As long as the breaker is rated based on the wiring gauge and distance, how is 2 x 14-50s different than 2 x 5-15s? If I overload the circuit the breaker trips, whether I'm plugging in space heaters or EVs.

As I said above, I literally did this for years when we had the Roadster UMC and Model S MC, a single car garage, and a heavily loaded electrical panel (standard 1950's Bay Area shotgun house w/ 100A service and tiny panel).

Well, if it's not ok (because physics is somehow different for EVs than space heaters), then I would actually do a 14-50 for your Tesla MC (since you already have that) and then get one of these for the Bolt:

Lectron Tesla to J1772 EV Adapter | 250V | 48 Amp

Lectron Tesla to J1772 Charging Adapter 48A. Compatible with Tesla High Power Wall Connector, Destination Charger, and Mobile Connector.

ev-lectron.com

That's because since the Tesla will be primary, it will be less messing with adapters. The Tesla J1772 works great but you have to get into the car or use your phone app to unlock it every time.

 

[Cosmacelf]

Why are 2 outlets on the same circuit not ok? I have multiple 5-15 outlets on the same 20A breaker. As long as the breaker is rated based on the wiring gauge and distance, how is 2 x 14-50s different than 2 x 5-15s? If I overload the circuit the breaker trips, whether I'm plugging in space heaters or EVs.

The reason this is disallowed in the electrical code is that the presumption is that high power circuits will be routinely used near their capacity. So, yeah, the circuit breaker would trip, but that isn't something you want to happen. I mean, now you have no power. How is that a good design?

120V 15A or 20A receptacles, on the other hand, do not routinely get used by equipment near their limits (think convenience outlets in a living room), but if they are installed in a location where they do, like in a bathroom which might have an 1800 watt hairdryer, or a kitchen which might have 1500 watt kettles, then the electrician is going to install that receptacle on its own breaker.

 

[jjrandorin]

Why are 2 outlets on the same circuit not ok? I have multiple 5-15 outlets on the same 20A breaker. As long as the breaker is rated based on the wiring gauge and distance, how is 2 x 14-50s different than 2 x 5-15s? If I overload the circuit the breaker trips, whether I'm plugging in space heaters or EVs.

As I said above, I literally did this for years when we had the Roadster UMC and Model S MC, a single car garage, and a heavily loaded electrical panel (standard 1950's Bay Area shotgun house w/ 100A service and tiny panel).

Well, if it's not ok (because physics is somehow different for EVs than space heaters), then I would actually do a 14-50 for your Tesla MC (since you already have that) and then get one of these for the Bolt:

Lectron Tesla to J1772 EV Adapter | 250V | 48 Amp

Lectron Tesla to J1772 Charging Adapter 48A. Compatible with Tesla High Power Wall Connector, Destination Charger, and Mobile Connector.

ev-lectron.com

That's because since the Tesla will be primary, it will be less messing with adapters. The Tesla J1772 works great but you have to get into the car or use your phone app to unlock it every time.

They are not, by code, period, for EV charging. People do stuff all the time thats not to code" but in this case its actually not safe because its too easy to overload. The next thing said is "well the breaker should pop if its overloaded" and while that is true, breakers also fail so should not be considered "I can do this not to code because the breaker will protect me.

5-15 120V outlets dont have anything to do with this and are allowed to be chained together like this.

 

[Cosmacelf]

Can other EVs make use of a 20A 120V receptacle?

Yes. You just need an EVSE that has an adapter for a 20A receptacle. Or can connect to a hardwired 120V, 20A wire like this one:

Connected EV chargers for home | Enphase

store.clippercreek.com

This one can plug into a NEMA 5-20:

https://www.amazon.com/Morec-NEMA6-20P-Adapterfor-100V-240V-Compatible/dp/B07Q5RD5TL

 

[CKwik240]

Yes. You just need an EVSE that has an adapter for a 20A receptacle. Or can connect to a hardwired 120V, 20A wire like this one:

Connected EV chargers for home | Enphase

store.clippercreek.com

This one can plug into a NEMA 5-20:

https://www.amazon.com/Morec-NEMA6-20P-Adapterfor-100V-240V-Compatible/dp/B07Q5RD5TL

While I can conceive EVSEs that's can do this, but how many other EVs are capable? It's been a while since I had a Volt, and it came with an EVSE that was limited to 12A, but I don't recall ever hearing of anyone being able to charge it at 16A.

Ultimately, the question is, what other EVs can do this? Surely they can plug in, but will they maximize the available current?