Why does my extension cord strategy fail?

[JonB65]

I've been trying put together an extension cord strategy that provides flexibility while minimizing components.

My thought was to start with a 30 ft, 14-50 extension cord - this would allow connection at a 14-50 outlet using the Tesla 14-50 adapter on the mobile charger. Testing this configuration resulted in successful charging.

I then thought that I could use this same extension cord for 5-15 charging by using a 5-15M to 14-50F adapter > 14-50 extension cord > Tesla 14-50 adapter on the mobile charger. When I put this combination together, the mobile charger will not light up. I have tried both GFCI and non-GFCI 120v outlets.

Why does the mobile charger not operate in this scenario?

Seeking to learn. Thanks.

 

[samps]

The 14-50 adapter on the mobile charger is programmed to pull 32A I think and the fact you have it plugged in to a 5-15 doesn't allow it to do so. In order to make your configuration work I believe you would need a 14-50M to 5-15F adapter at the end of the extension cord and then use a 5-15 adapter to the mobile charger. But at that point you might as well just get a regular 5-15 extension cord.

 

[MattM24]

I've been trying put together an extension cord strategy that provides flexibility while minimizing components.

My thought was to start with a 30 ft, 14-50 extension cord - this would allow connection at a 14-50 outlet using the Tesla 14-50 adapter on the mobile charger. Testing this configuration resulted in successful charging.

I then thought that I could use this same extension cord for 5-15 charging by using a 5-15M to 14-50F adapter > 14-50 extension cord > Tesla 14-50 adapter on the mobile charger. When I put this combination together, the mobile charger will not light up. I have tried both GFCI and non-GFCI 120v outlets.

Why does the mobile charger not operate in this scenario?

Seeking to learn. Thanks.

The problem is that Tesla uses the Line-Line on the 14-50 to get its power from 240V.
When you try and use a regular 14-50 to 5-15 adapter, the 5-15 is powering the line-neutral.
This leaves the Tesla adapter trying to draw power from the line-the same line, which is nothing.

If you want to do this, EVSEadapters sells a 5-15 to 14-50 adapter for EV use only.

 

[JonB65]

Thank you both for the helpful information.

 

[MattM24]

You do need to also manually turn down the charge current in the car to 12A or less.

 

[JonB65]

You do need to also manually turn down the charge current in the car to 12A or less.

I did try that. Did not work.

 

[MattM24]

I did try that. Did not work.

You need to have the special adapter as well.

This is the one I have.

NEMA 5-15P/5-20P to 14-50R 120V Adapter for EV, 3 ft. – EVSE Adapters

www.evseadapters.com

 

[JonB65]

Just a quick follow-up. I did get this all worked out thanks to your advice. Much appreciated!

 

[mswlogo]

This is why some camp sites ban EV’s

You should never depend on turning current down in the car to prevent circuits from tripping. Because humans forget.

 

[Dbear1000]

How did you end up resolving your extension cord issue with the 5-15 outlet? I am facing a similar issue with a 5-20.

 

[JonB65]

Yes. I bought a couple adapters from EVSE as @MattM24 mentioned above. All worked great. Though I actually have never used these. It was more of an experiment/learning process for me. I ended up buying a regular 5-15 extension cord for use with normal house outlet, and will use the 14-50 extension cord with proper adapters if I ever need to go higher. That hasn't happened in over two years of owning the car. But, I did learn some stuff along the way.