Question on charging. [can I run an extension cord from my apartment window to my car?]

[Miraj]

I live in an apartment where I cannot have the charger installed.
So I am thinking to buy cable like and extension cord which is equivalent to the cable we get with the Tesla and use wall outlet to charge my car. I can run the cable from
My window to my car and need only 25 feet long cable. I have asked Tesla if they have extension cable and they said they do not have it. I have looked it up on amazon and it’s available but problem is I need three prong end on the cable in order to use my wall outlet.
Any suggestion in this would be extremely helpful.
Please note I am not a tech savvy person so trying to ask this question how I understand it. If there is any other suggestions please let me know. Cable found on amzon with 4 prong is this one. NEMA 14 cable

 

[Tam]

...wall outlet...

Tesla does not recommend an extension cord.

If you insist, you need to make sure the size of the wire is big enough to reduce the electrical fire hazard.

What does your wall outlet look like? Is it a normal 120V for regular electronic equipment like TV and refrigerator?

Or a bigger outlet that is 240V, not for regular electronic equipment like TV and refrigerator, but for a heavy-duty appliance like an electric clothe dryer?

A picture of your wall outlet would be helpful.

 

[CarlThompson]

Tesla does not recommend using an extension cord and running one out your window of your apartment over property that is not your own seems like a bad idea. What if someone trips over the cord? What if the apartment groundskeeper runs over it with a lawnmower or hits it with a weed wacker?

If I lived in an apartment I'd just charge my car at a supercharger when needed.

 

[jjrandorin]

This is not something you are going to want to do. Any outlet in your apartment that you will be trying to "run out the window" to your car, is going to be on a circuit with several other items.

Since you mention you are not a technical person, I will skip the even semi technical reason, and say that multiple things on the circuit you would be trying to charge your car on would likely trip your breakers, and that doesnt even count the social issue of having a plug hanging out of your window (possible theft, extra draft into your apartment someplace it actually gets cold, etc).

You may not know this, but plugging your car into an outlet in your apartment would, at best, give you about 5 miles of charge an hour, not counting when its very cold out, so its not like you would be plugging in "for an hour" or something.

This is not something you should be planning, in the slightest. You will need to charge via superchargers, or move to a place where you can get charging. Putting an extension cord from your apartment window to your car is not something you should be contemplating at all.

 

[Rinzler]

The only cable I would use is from GearIT. It can be found on Amazon and is not cheap but is proper sized gauge cable. That cable is extremely heavy also and your apartment manager will more than likely give you a written notice for doing that. Your best bet is to find local superchargers or use free destination chargers.

"GearIT 50-Amp 50-Feet 250-Volt RV Extension Cord for RV"​

 

[pipp]

It would be interesting to know more of the salient facts and also what you end up doing as a solution. Rinzler was the first poster to mention an apartment manager (or maybe the landlord is the apartment manager). Even if all the above reasons for not extending weren’t legitimate, you still wouldn’t want to do this without landlord approval. Would you? It might be the apartment manager/landlord who let you know in the first place that there wouldn’t be any big help coming from them to charge tenants’ cars, so maybe you’re considering an end-run? With all the potential hazards here the last thing you would want is complete and total liability because of the fact that you didn’t get landlord approval. But like I said, there’s just a lot of interesting little detail facts about this case that could bring more perspective to it. Good luck and report back!

 

[jkirkwood001]

To all those recommending against it, I have done so at our cottage since 2018 with no problems - summer and winter. Below is a photo where my car parks, although it's not plugged in here. I run a standard ~50 foot extension cord from the cottage's outdoor 110v plug and set the charge max to 10 amps instead of the 12 available. It works great because I'm usually there for the weekend and so a trickle charge is fine - I can charge from 50% to 90% within 3 days. In your case, it might work well too if you're only driving under 30 miles per day. Consider if you really need faster 220v charging. I can't remember offhand, but I seem to recall 110v charges around 10 KM (~6 miles) per hour, so overnight might be enough for your city driving. I would certainly try it.

 

[Rocky_H]

To all those recommending against it, I have done so at our cottage since 2018 with no problems

People were recommending against it for a variety of reasons that don't apply to your situation:
1. Out a window instead of an exterior outlet
2. Public space where other people are walking around
3. Needing permission of a landlord

You don't have any of these issues because it's a place you own, where only you will be, so sure, that's a pretty good reasonable use case.

 

[dansev]

Like JKirkwood, my situation doesn't apply, but I'm surprised to hear that absent the OP's circumstances, an extension cord is not OK. I have been using a heavy-duty 15A, 100 foot extension cord that I originally researched and bought for my electric snow blower. Same kind of requirements: needed to be able to slam as much electricity down it as possible, even in the cold, and not lose anything in the process. The cable is a "Yellow Jacket 2885 12/3 Heavy-Duty 15-Amp Premium SJTW Contractor Extension Cord with Lighted End." When we bought a small cottage on Cape Cod, I used that extension cable from an outlet on its own circuit in the crawl space. It never gets overly warm when charging and I'm always a bit surprised at the speed: at least 4mph, even in the winter. I've used it about 150 times in the last 18 months without ever thinking twice about the safety. Is there something wrong with this? Or is it just out of an abundance of caution that it is frowned upon? If someone uses a more pedestrian cord, maybe the fire hazard is more likely? (Fortunately I have a wall connector being installed this winter.)

 

[Rocky_H]

but I'm surprised to hear that absent the OP's circumstances, an extension cord is not OK. [...] Is there something wrong with this? Or is it just out of an abundance of caution that it is frowned upon? If someone uses a more pedestrian cord, maybe the fire hazard is more likely?

Yes, it's abundance of caution. Most people have no clue. If Tesla tells people extension cords are fine, people will use the most pathetic pieces of cheap garbage they can find, melt something or start a fire and then blame Tesla. They don't want any part of that, so they just tell people not to do it.

The cable is a "Yellow Jacket 2885 12/3 Heavy-Duty 15-Amp Premium SJTW Contractor Extension Cord with Lighted End."

That is the very same one I got. That is super solid with 12 gauge wire. The only two supposedly "Heavy Duty" extension cords I had before I got my EV were 16 gauge wire, which is definitely not sufficient. So you know what you are doing, and that's fine.

 

[jjrandorin]

@jkirkwood001

Like @Rocky_H Said, my recommendation was "no" because of the reasons that he laid out. your situation is different, and in your case, if you were asking (which you are not, I know), I would have said "plugging in from an external outlet at your cottage sounds perfectly fine, just make sure to get a robust extension cord".

The OPs situation is very much different, as already mentioned.

 

[jkirkwood001]

@jkirkwood001

Like @Rocky_H Said, my recommendation was "no" because of the reasons that he laid out. your situation is different, and in your case, if you were asking (which you are not, I know), I would have said "plugging in from an external outlet at your cottage sounds perfectly fine, just make sure to get a robust extension cord".

The OPs situation is very much different, as already mentioned.

I disagree that they are very different, and I suggested 110v may be sufficient for OP rather than the less recommended extension of 220v. I think this is a helpful contribution - based on my real experience - so I don't think you need to be so defensive.

 

[blkswn]

I do this when traveling with a 50ft 120v 20-amp chord when using AirBnb's and use the 120v outlets. Depending on the quality of the wiring at the outlet, I've gotten messages on the car that say an extension chord is detected and to please remove it.

 

[Rocky_H]

If it detects a "chord", you need to play musical chairs with trying different outlets.

 

[KenC]

The OP needs to give more details on

I live in an apartment where I cannot have the charger installed.
So I am thinking to buy cable like and extension cord which is equivalent to the cable we get with the Tesla and use wall outlet to charge my car. I can run the cable from
My window to my car and need only 25 feet long cable. I have asked Tesla if they have extension cable and they said they do not have it. I have looked it up on amazon and it’s available but problem is I need three prong end on the cable in order to use my wall outlet.
Any suggestion in this would be extremely helpful.
Please note I am not a tech savvy person so trying to ask this question how I understand it. If there is any other suggestions please let me know. Cable found on amzon with 4 prong is this one. NEMA 14 cable

That NEMA 14-50 cable will work, but unless you have a 4-wire electric dryer in your apartment, you'll still need an electrician to install an outlet to use that cord. And, if you're going to get an electrician, maybe you should consider putting an electrical box, outdoors. But, you'll need the approval of whomever owns/rents out your apartment.

Since you're asking about a 3-prong, it seems obvious you don't realize that the 14-50 is huge compared to your standard 120V plug.

Basically, you need to give us more info on what you need in terms of daily charging and maybe a picture of what you're thinking of doing, because there are lots of issues to address, like public safety, approval from apartment owner, etc., etc., etc.