Charging in detached garage at apartment

[Verva12]

Hey guys,

I live in an apartment and my garage is detached. There are 5 garage units and it’s a free standing building. I have one regular outlet above my garage door opener. I am planning on using the included regular charger that get around 4 miles per hour of charge. This would be fine for my daily driving needs.

I have been approved by the complex to charge. However, before I finalize my order, I am wondering what final questions I should ask. I don’t want to trip the breaker when charging. I am going to ask to look at the breaker wherever it is. What should I look for in terms of amps etc. to ensure it will charge and not cause any issues.

Thanks!

 

[arghx7]

It will automatically limit to 12 amps on a standard NEMA 5-15 outlet. If you have a 5-20 in there, get the adapter to charge faster from the Tesla store.

 

[xcat]

1) check if the outlet is on its own breaker or shared between the other units
2) if on own breaker, check the breaker size. If 15 amps, use what comes w the car. If 20 amps get the adapter mentioned above to charge a bit faster and possibly convert your outlet to a NEMA 5-20r

 

[Verva12]

Here is the breaker on the back of the garage. And also the socket I have.

 

[Verva12]

 

[MrMassTransit]

Looks like you have a 5-15 outlet behind your door opener, but you have a 20 amp breaker. I'd verify the wiring is 12 gauge or larger and if so, you can swap that outlet out for a 5-20 outlet, which will let you charge a bit faster if you get the 5-20 plug from Tesla.

 

[ChrisMPK]

It also looks like there is plenty of breaker space and wiring is totally open. I'd explore getting a larger circuit installed. You could get a quote and offer to split it 50/50 with the apartment owner if it's reasonable. It couldn't hurt to ask.

The biggest concern to me would be that other outlet is on the ceiling.

 

[brkaus]

It also looks like there is plenty of breaker space and wiring is totally open. I'd explore getting a larger circuit installed. You could get a quote and offer to split it 50/50 with the apartment owner if it's reasonable. It couldn't hurt to ask.

The biggest concern to me would be that other outlet is on the ceiling.

It’s still pretty limited. The main breaker in the sub-panel is 40a.

I agree with above. Get a quote. Should be easy with all exposed interior. I’d see if I could get a 5-15 or 6-20 installed.

I’d also offer the owner some money to cover the electric. Having charging at home is well worth it.

 

[Big Earl]

A NEMA 6-20 (240 volts) would be good in this situation. 3.8 kW charge rate adding approximately 15 miles per hour. Should be fine on the 40 amp main if your neighbors are only using garage door openers and lights. If they also have EVs or other high-draw appliances like space heaters, you could run into problems.

 

[MrMassTransit]

If there's panel capacity, a 6-20 would be a great option. Alternatively (assuming capacity exists), you could also install an HPWC or any other hard-wired EVSE if you wanted to go that route. It wouldn't charge any faster, but some would argue that a wall-mounted charger is more convenient.

I agree with the others that if there's capacity, an additional outlet or a wall mounted EVSE should be relatively reasonable to get installed. I'd get a few quotes but it seems like you have options.

 

[Snow Drift]

I had a similar situation, although no access to the breakers. We used an appropriate extension cord and the UMC for a year, without issue.

Here is the cord: https://www.amazon.com/gp/aw/d/B07GQ8RPGF?psc=1&ref=ppx_pop_mob_b_asin_title

My wife had a 10 mile commute to work and the 120v (5mi/hr) charging was perfect. We were also able to take longer drives on the weekends without any anxiety.

Make sure to have the car scheduled to charge in the early AM in winter so your battery is warming before work. You want as much regen braking as possible.

We never had a problem with power surges or anything. It just functions like any other basic device plugged into an outlet.

 

[Verva12]

Thanks for all the feedback. I am going to ask them today how much it would be for the various upgrades. I’m guessing that they will have to ask upper management since it is kind of chain apartments. I will report back once I talk to them. I know they told me that I would need to pay for anything new installed. Does anyone have an idea how much any of this would cost if they provide a quote?

Thanks

 

[MrMassTransit]

If there's panel capacity, adding a 6-20 should not be expensive given your setup. I'd imagine no more than $300-$400 depending on your market, potentially as little at $250. To bring an electrician out for just that will probably be on the higher end of the range, but if they had other work to do at the site, I could see it being as little as a $150 incremental cost.

Swapping the 5-15 for a 5-20 is an even smaller job and could be done by a handyman rather than an electrician.

If you needed to upgrade the wiring into the panel, you're talking about a much bigger job - probably over $1k but a lot would depend on what the situation was at the main panel that the sub panel is connected to and how easy it would be to make a new wiring run.

Also, if you potentially would be in a situation where you'd be required or want to reimburse the owner for power used, you might want to consider installing a meter as part of the job. Something like this would allow you to track electric consumption. I'd imagine installing it would only add $50-100 to the job, though it would be much more expensive to call an electrician out to add a meter in the future.

 

[davewill]

One thing nobody's mentioned is that you describe the building as having 5 garage units, but that panel only has 4 circuits coming out of it. That may mean that two of the garages are sharing a single 20a circuit. If you can, you should determine if your garage is one of them. If so, you'll want to be careful about drawing the max (like using a 5-20 adapter) so that you don't blow a breaker if your neighbor opens their garage door while you're charging.

It may even be that the building is wired so that all the lights are on two circuits and all the plugs on two others, or one of the circuits may be for outdoor plugs, or ???. It would be worth the effort to suss that out, if possible. It might not even be that hard as the wiring seems to be visible in the unfinished interior.

As long as you're the only EV, I would think that plugging into the existing 5-15 would be no problem even if one of the odder scenarios is happening.

 

[Sophias_dad]

Assuming that's 12 gauge wire(and I really hope it is, since its not supposed to be on a 20 amp breaker without 12 gauge or better), even having two door openers on one 20 amp circuit would likely be fine. Even changing the outlet to a 5-20 means the car won't ask for more than 16, and a liftmaster professional chain drive takes only 4-5 amps worst case, and I imagine that's only for a second or two at startup.

I agree with others, though... See if you can get a nice 20-30 amp dedicated 240 volt circuit...

 

[Verva12]

Thanks. Spoke with maintenance today. He is gonna see about getting me a dedicated 15-20 amp line that wouldn’t cost too much. I would have to pay all the costs. I wouldn’t mind trying it even on the regular wall socket and upgrade if I need to. I told them to check into a 6-20 as well

 

[MrMassTransit]

As I understand things, if a dedicated 5-20 is possible, a dedicated 6-20 should also be possible (as the load 20 amps would be the same and it is clear you have breaker spaces available in the panel). You’ll see an enormous improvement going from 5-20 to 6-20, so if you are going to pay any sum to have a dedicated outlet installed, I strongly recommend going the 6-20 route.

 

[eevee-fan]

Agreed best to discuss with management on upgrading but know that upgrading the power may upset the management (higher common area fees). If you are able to use the existing outlet and charge at 4 miles per hour, that's still probably 48 free miles a day plus some make up hours on the weekend. If you need more charge, then go to a public charger.

Alternatively, see if your state/city or power company has rebates that will reimburse for installation of public chargers / multi dwelling units. Would be nice to have a dozen parking spots for EV parking (perhaps set as shared power of 6.6 KW per pair of EVSE so when 2 EVs are charging, each get 3.3 KW) to keep the operating cost low. 3.3 KW is about 12 miles per hour of range. I recommend shared power if that would allow more plugs to be installed - nothing more frustrating than to have the one charge at the complex always in use by 1 PHEV.

 

[spbond0079]

Thanks. Spoke with maintenance today. He is gonna see about getting me a dedicated 15-20 amp line that wouldn’t cost too much. I would have to pay all the costs. I wouldn’t mind trying it even on the regular wall socket and upgrade if I need to. I told them to check into a 6-20 as well

Hi, I am in the similar situation as yours. I am contemplating in getting a tesla and have similar outlet with the garage door opener. I am going to inquire about the circuit. Wanted to know how things worked out with your situation?