Source
r/TeslaLounge•
scmcomp

Split Single 120v to Two?

Charging

Hey everyone, hope this is the right sub for this. Was going to post in r/Teslamotors, but their rules said questions go here. I've been searching for a direct answer on this and haven't been able to find one. Hoping someone here knows.

I live in an apartment with detached garages. Inside the garages there is only one outlet with a single plug. The plug is connected to the garage door opener. I wanted to plug my Tesla into the 120v outlet and just charge that way, as I don't drive much and the 3 miles per hour is enough for me. However, doing so would mean I'd have to leave the garage door opener unplugged and manually open/close the garage door. I was wondering if it's safe to use a splitter to turn the single plug into two so I could have the Tesla and the garage door opening plugged in at once? Something like this: https://www.amazon.com/dp/B0000510R4/ref=cm_sw_r_apan_i_M6590A1SN7FYR46BXQH0?_encoding=UTF8&psc=1

I don't believe garage door openers draw too much power, and I could reduce the draw of the Tesla if neccesary to avoid tripping the breaker. I just want to make sure this isn't a fire hazard or something that could damage the Tesla.

Edit: Unfortunately I don't have access to the breaker box, so I can't shut it off to switch the outlet out.

Posted Apr 10, 2022, 8:02 PM UTC · edited

217
charonpdx:m_sans::o_sans::d_sans::e_sans::l_sans: :S: :O: :I:•

Any "one outlet to two outlets" splitter should work fine, as long as its properly rated for 15 Amps. Something like this from Monoprice

One warning, though - if your apartment complex has multiple garages all in a row, they might all be on one single circuit, so if you and a neighbor both plug in EVs, you might trip the breaker.

The garage door opener shouldn't draw too much to be a problem, although to play it safe, you might want to stop charging in the app before using the garage door opener to get in the garage.

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scmcompOP•

Awesome! Thanks for the heads up I hadn't thought about the garages potentially being connected to the same breaker. I think I'm safe for now because EVs aren't very common where I live, but ill definitely keep it in mind

1
ss68and66•

It's more than likely a 15amp circuit, you'll need to change the plug to a dual outlet and a new faceplate you can leave both plugged in just unplug the car or stop the charge before using the garage

1
scmcompOP•

Thanks for your reply! Unfortunately I don't have access to the breaker box, so I can't shut it off to switch out the outlet.

1
davispw•

I would think the breaker box must be accessible somewhere in case of emergency.

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scmcompOP•

It is, but it's a locked box on the side of the garage, and the apartment won't allow me to change things.

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ss68and66•

You can switch it out "hot" but be warned you can easily get electrocuted/shocked although mild I'm not sure how it would affect you.

0†
davispw•

Terrible advice.

5
Exciting-Giraffe-908•

Agree. Unless you are very experienced with electrical wiring, I would not recommend working in a "hot" box. I've watched my professional electrician do it, but I would never attempt it myself, and he agreed.

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[deleted]•

[removed]

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MBSMD•

I would think it would be ok. The garage door is very unlikely to be in use while simultaneously charging the car, so I think it would be ok. I’d recommend stopping the charge if you need to open the garage door for any reason while the car is actively charging. You may want to limit the car to only 10 or 12 amps to be safe. Make sure that device (which I think is basically a surge protector) will handle that much amperage. Otherwise just get a heavy duty passive double outlet splitter and abide by the guidelines I suggested above.

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scmcompOP•

Awesome thanks for the advice that helps a lot!

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jpapon•

I would expect a garage door opener to actually have a pretty significant draw for a very short period when the motor first engages and it needs to accelerate the door. This might be enough to trip a 15amp breaker if you’re also charging. In theory you could have a splitter that automatically temporarily disconnects the charger when the garage door comes on, but I don’t know if there’s an off the shelf splitter that does that.

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scmcompOP•

I'm thinking to be safe I'll turn off charging in the app before I open the garage door

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MotherAffect7773•

When I first got my car I did this as the fridge, freezer, and car were too much for the wall outlets in my garage (house). I used a retractable cord (don’t do this!!) until I noticed it was getting really warm (25’ coiled up and probably 16 gauge wire, 1kW is too much!). I then switched to a 6’ cord hanging from the ceiling, and never had a problem. Breaker never tripped while simultaneously operating the opener while charging.

Standard connector pulls 12A max, 15A breaker will take some time to trip, and the opener will demand the excess (motor starting) only for a moment, and then apparently not long enough (my experience) to trip the breaker.

I have (as most of us do) since installed 14-50 receptacles for the improved charge rate/speed. I know, not an option for you, just sayin’.

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scmcompOP•

Thanks for the advice! Glad to hear it seems like it will work as long as I use a shorter cord like you did

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