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Charging outdoors on an extension cord - 10-30 or 14-30?

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So I don't have a garage and have to charge outdoors. Currently I charge with a NEMA 5-15 adapter through a 12-gauge extension cord to a generic 110V outlet. I recently had a 30A line put in, but the electrician put on an L14-30R receptacle which as far as I can tell is typically used for generators. I want to have this receptacle changed to either a 10-30 or a 14-30R and run an appropriate extension cord and an appropriate adapter.

The problem I'm having is this:

* For 10-30, there are lots of extension cables that appear to be made for RVs, but 10-30 has no ground and this will be run outdoors in a rainy region. Is this dangerous?
* For 14-30, there is a ground, but extension cables appear to be few and far between and expensive. They appear to be mostly made for dryers and as such there isn't a huge market for dryer extension cables.

I know ideally a 50A line would be appropriate, but that's not what I have, so I'm working on 30. Is there anything I'm missing? Which interface should I be using to charge my car outdoors via an extension cable?

Thanks
 
New 10-30 installations are not allowed since 1996. You can only replace an existing 10-30. Since NEMA 10 devices don't have a separate ground I would definitely not use one in this manner, anyway.

A 30A connection is not really a handicap unless you intend to need to charge from 0 to 100 in a short overnight stretch. EVSEadapters has 14-30 extension cords up to 50'.~All Other Adapters, Splitters, & Cords – EVSE Adapters

If you're going to go the extension cord route be sure you have a GFCI breaker on that circuit.

Generally, the correct response is to hire an electrician to install an outdoor outlet or Tesla Wall connector.
 
The UMC is perfectly safe with the 10-30 adapter and doesn't even use the 4th pin on a 14-30, so there is no functional or safety difference between the two.

That said, this is really not the way you should be going about things. The UMC itself is not particularly weatherproof and you definitely don't want the brain box or its connection to the extension cord out in the elements.

How long of an extension cord do you need? Is a wall connector out of the question?
 
For the 14-30, the most inexpensive extension cords are the L14-30, as you have.

The reason is these cords are mass-produced for generators, but no one uses a 40-100ft cable for their dryer.

This 40 foot cable is a good deal, and you can connect two of them if needed, or get the longer ones. I wrapped the joint in some plastic bags when I did that. The 100 foot cable is hard to find, and more expensive per-foot.

https://www.amazon.com/gp/product/B07FT4M77B

Then get one of these:

L14-30 Twist-lock Adapter for Tesla Model S/X/3/Y Gen 2 – EVSE Adapters

Other than that, long wires and adapters are not cheap, nothing you can do about it.

The 14-30 offers both 240v and 120v connections, so the voltage drop over the 120v side is higher as a percent, especially when using the full 30A (whereas the Tesla only uses 24). That's probably why you don't find the 100 foot cable.

Voltage Drop Calculator

Voltage Drop Calculator

I suppose that connecting two smaller extension cords is potentially hazardous, so you have to do your own calculations and research I guess.
 
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New 10-30 installations are not allowed since 1996. You can only replace an existing 10-30. Since NEMA 10 devices don't have a separate ground I would definitely not use one in this manner, anyway.

A 30A connection is not really a handicap unless you intend to need to charge from 0 to 100 in a short overnight stretch. EVSEadapters has 14-30 extension cords up to 50'.~All Other Adapters, Splitters, & Cords – EVSE Adapters

If you're going to go the extension cord route be sure you have a GFCI breaker on that circuit.

Generally, the correct response is to hire an electrician to install an outdoor outlet or Tesla Wall connector.

It was an electrician that did the work, but rerouted a prexisting 30A breaker to a new circuit per my request. A Tesla Wall connector wouldn't make it to the driveway. Thinking about going 14-30, but as you showed, the extension cords are fairly costly, but I guess that's a small price for safety.
 
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For the 14-30, the most inexpensive extension cords are the L14-30, as you have.

The reason is these cords are mass-produced for generators, but no one uses a 40-100ft cable for their dryer.

This 40 foot cable is a good deal, and you can connect two of them if needed, or get the longer ones. I wrapped the joint in some plastic bags when I did that. The 100 foot cable is hard to find, and more expensive per-foot.

https://www.amazon.com/gp/product/B07FT4M77B

Then get one of these:

L14-30 Twist-lock Adapter for Tesla Model S/X/3/Y Gen 2 – EVSE Adapters

Other than that, long wires and adapters are not cheap, nothing you can do about it.

The 14-30 offers both 240v and 120v connections, so the voltage drop over the 120v side is higher as a percent, especially when using the full 30A (whereas the Tesla only uses 24). That's probably why you don't find the 100 foot cable.

Voltage Drop Calculator

Voltage Drop Calculator

I suppose that connecting two smaller extension cords is potentially hazardous, so you have to do your own calculations and research I guess.

This looks like a good middle ground. I didn't know there were L14-30 Tesla adapters. Thanks
 
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81E1hJl8yNL._AC_SX679_.jpg


Less likely trip you!
 
To the OP, a problem with the recurrent use of temporary use extension cables (no matter the cost) is that over time the flexing of the cable will allow breakage of the individual conductor strands. This creates internal resistance and adds to the overall voltage drop, IE, where connected to a 120 volt supply, the useful voltage may become less to the point, charging is affected...
 
To the OP, a problem with the recurrent use of temporary use extension cables (no matter the cost) is that over time the flexing of the cable will allow breakage of the individual conductor strands. This creates internal resistance and adds to the overall voltage drop, IE, where connected to a 120 volt supply, the useful voltage may become less to the point, charging is affected...

That depends on how often you move the extension cord. I'd think that using it temporarily and coiling/uncoiling it would do much more damage. He can always buy new cords in 5-10 years if that happens.

The big problem with non-temporary extension cords is lawnmowers. Ever time that you mow the lawn you'll need to mow around them or put them aside.

I'm not sure if the OP is aware that he should have dug a trench and installed an outlet or HPWC on a post in the ground, but that will pose challenges for him, having already done the electrical work.
 
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For the 14-30, the most inexpensive extension cords are the L14-30, as you have.

Just wanted to add my voice in support of @user212_nr's post. He's got it spot on. The EVSE L14-30 adapter + an L14-30 is the most cost effective way to do what you want, and honestly, I really like the locking connectors. The positive, secure connection always gives me the warm fuzzy instead of a possibly loose bladed connector.
 
Just wanted to add my voice in support of @user212_nr's post. He's got it spot on. The EVSE L14-30 adapter + an L14-30 is the most cost effective way to do what you want, and honestly, I really like the locking connectors. The positive, secure connection always gives me the warm fuzzy instead of a possibly loose bladed connector.
I agree that locking connectors are better. However, they do not eliminate the need to regularly check for heating. All plugs and sockets should be checked regularly for heating after about an hour of continuous use to make sure they are still just warm to the touch. If you can't hold your hand on it for 10 seconds straight without discomfort, it's too hot.