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J1772 extensions for home charging safe?

smashweights

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Hey all! With the recent snow, I bit the bullet and parked outside so my wife could have the garage. Managed to sneak the L1 portable charger under the garage door to try and keep it plugged in the cold. It got me thinking if I could just get a J1772 extension for my Tesla UWC so I could stay on my hardwired L2 charger when I'm the driveway. I was looking at the A2Z extension, seems to have some official "certifications" and is rated for 240v/48A (would probably cap charging at 32A while using an extension.

Is this a safe option?

Rivian R1T R1S J1772 extensions for home charging safe? 3534
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Time2Roll

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Generally I would consider them safe for temporary use.
However I would not be excited about closing the garage door on a cable.

Far prefer to have an exterior charge unit or 240v outlet.
 
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smashweights

smashweights

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I have the portable but only 120v outside and the portable charger would be buried in snow
 

HaveBlue

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Generally I would consider them safe for temporary use.
However I would not be excited about closing the garage door on a cable.

Far prefer to have an exterior charge unit or 240v outlet.
Many garage doors just have a plastic weatherstrip gasket on the bottom that conforms.
 
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smashweights

smashweights

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Many garage doors just have a plastic weatherstrip gasket on the bottom that conforms.
Yes we have a thick rubber gasket on the bottom
 

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Dave Cundiff

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I bought a printed Garage Door Cable Pass Through and keep it in with my portable charger.
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That tunnel looks like a highway for mice to get into the garage, @KBabione. I hope that hasn't been your experience. Is there something inside the tunnel that limits the passageway diameter to within a few millimeters of the cable's diameter?

For outdoor charging from a charger in the garage, I have (1) a couple small narrow strips of 1/2" plywood that go on either side of the cable; (2) a conforming plastic strip on the bottom of the garage door; and (3) bait stations under the front of each Rivian, which puts the bait stations about 5 feet in front of the garage door.

So far, I don't think the charging cable has allowed any mouse entry. A mouse infestation 2-3 years ago had a different point of entry, which is now sealed. No recurrence of mice in garage or house.

Best wishes!
 

KBabione

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That tunnel looks like a highway for mice to get into the garage
I never thought about mice - Thanks for the heads-up. The actual one I have (this was just an example - the Etsy store from which I bought mine is taking a break), probably allows about 1/4" around the cable. I typically only use my portable charger (with permission) when I'm staying at an AirBnB or VRBO so it's not for long-term use. I also bought one for my in-laws because they (very nicely) put in a L2 charger in their detached garage when we bought our Rivian and I need to run the charging cable under the closed door. There, because the charging cable is thicker, it's an even smaller gap. I will, however, now think about it and look more closely when I'm using it. Thanks again!
 

Dave Cundiff

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My understanding is that mice and rats can deform their skulls and bodies enough to get through VERY narrow openings. I try not to take chances.

Best wishes!
 

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DCFC

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Keep the current low. Heat generation is to the square of current. 48A will make 4x the heat of 24A. Power = volts * amps. Volts = amps * resistance. So heat generated = power= amp^2 * resistance.
 

mkhuffman

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I use the A2Z extension on my 48 Amp Emporia EVSE. It has worked great until a month or so ago. I think it is detecting an overheat situation and stopping the charge. It happens after charging for more than a hour, which is why I think it is heat related.

Regardless, it's safe and I would recommend it if you need it. I am not a fan of running the cord under the door either, mainly because of rodents.
 

hammick

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I have one that I made using a charging cable from a crappy Chinese charger. The cable was quality though. Then I bought a J1772 input on Amazon and made a cable. I use it to charge at 16 Amps. 50’ of cable is probably too long for 48 amps.
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