Burning 25ft 10/3 cords using my mobile connector in the rain with a 120v outside GFCI outlet

[petercc9]

So yes I am using a standard 120V GFCI outlet. No, I don't have a garage. Outlet outside on side of house with a clear cover (standard new house install)

Driveway distance from outlet exceeds mobile connector cord length so using heavy 10 gauge 25ft extension cord.

Anybody else burning out extension cord wires?

So I try my best to keep where the cord connects to the mobile charger dry.

But I still manage to fry cords. I'll get a notice the car has stopped charging and then see a black mark on the ground on the female side of the extension cord. The extension cord connector is clear so you can see the damage.

I assume water infiltration is causing grounding.

So that's 3 spots where it can fail. At the outlet (which with the cover up could get wet), at the extension/Mobile connection (my top suspect), and of course at the charger door.

My fear is someday I'll short my mobile connector and be basically helpless.

So to remedy this I have
1) purchased a new outlet cover that has a hole on the bottom so you can close it when in use.
2) purchased these small (like 2.5mm) gaskets that you can slip between the extension cord/mobile connector to supposedly help prevent water infiltration.
3) need ideas on the charger door area

Any suggestions?

 

[DBeckwith]

Have an electrician add a outlet close enough so the charging cables reach without an extension cord. The simple reality is it is unsafe to use an extension cord to charge an electric vehicle.

 

[Jim R]

Consider having a Wall Charger installed by an electrician. Yes, it will dent your wallet for a while, but the convenience will last for ages.

 

[BroncoAZ]

I agree with getting a wall charger installed, but not everyone can or wants to do that. My buddy ran his model 3 for three years off only 110v. He worked from home and only used the car every few days, he didn’t want to spend the money on the electrical upgrades in his old house. It was always fully charged (80%) on 110v for his needs.

You need to stop the water from getting in the extension cord to mobile connector junction. The 10 gauge extension cable should be fine, the wiring in the wall from the panel to the outlet isn’t 10 gauge. Wrap the connection from the extension cord to the mobile connector in electrical tape to keep the water out. Another option would be to elevate the connection off the ground and put a bucket or plastic container upside down over the connector. You could also try one of the charge cable extensions, they may have better waterproofing.

Lectron Tesla EV Extension Cord | 20 ftDefault Title

Lectron Tesla Charger Extension Cable Extra 20 Feet to Your Charger. Compatible with Tesla High Powered Wall Connectors, all generation of Destination Chargers.

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[boones]

Could a product like this be helpful? Amazon.com

 

[robaross]

Wrong gauge

 

[Iron]

So yes I am using a standard 120V GFCI outlet. No, I don't have a garage. Outlet outside on side of house with a clear cover (standard new house install)

Driveway distance from outlet exceeds mobile connector cord length so using heavy 10 gauge 25ft extension cord.

Anybody else burning out extension cord wires?

So I try my best to keep where the cord connects to the mobile charger dry.

But I still manage to fry cords. I'll get a notice the car has stopped charging and then see a black mark on the ground on the female side of the extension cord. The extension cord connector is clear so you can see the damage.

I agree with getting a wall charger installed, but not everyone can or wants to do that.

Am I alone in thinking this is just crazy? Dude, stop rolling the dice, spend the money and get it properly fixed. EVs burn hot and are hard to put out. House fires suck too.

Not everyone should buy an EV if your situation is not conducive to owning one. Prior hard consideration should be given before pulling the trigger, esp when it comes to charging, vs becoming danger to yourself and those around you.

 

[ewoodrick]

So yes I am using a standard 120V GFCI outlet. No, I don't have a garage. Outlet outside on side of house with a clear cover (standard new house install)

Driveway distance from outlet exceeds mobile connector cord length so using heavy 10 gauge 25ft extension cord.

Anybody else burning out extension cord wires?

So I try my best to keep where the cord connects to the mobile charger dry.

But I still manage to fry cords. I'll get a notice the car has stopped charging and then see a black mark on the ground on the female side of the extension cord. The extension cord connector is clear so you can see the damage.

I assume water infiltration is causing grounding.

So that's 3 spots where it can fail. At the outlet (which with the cover up could get wet), at the extension/Mobile connection (my top suspect), and of course at the charger door.

My fear is someday I'll short my mobile connector and be basically helpless.

So to remedy this I have
1) purchased a new outlet cover that has a hole on the bottom so you can close it when in use.
2) purchased these small (like 2.5mm) gaskets that you can slip between the extension cord/mobile connector to supposedly help prevent water infiltration.
3) need ideas on the charger door area

Any suggestions?

If the plug is leaving burn marks on the ground, my first guess is that the GFCI is faulty. AFAIK, it should NEVER do that. That's an example of a LOT of stray electricity floating around. And that's deadly.

A plug cover should help as @boones suggested or something like https://www.amazon.com/Waterproof-W...sprefix=extension+cord+co,aps,199&sr=8-4&th=1

 

[Jim R]

Another thought as an interim measure - One reason cords burn or melt is when too much current flows through them. Limit your charging amps with the app. A 115V, 15 amp circuit is likely what you are using. Limit the current to 80% of that 15 Amps, which is 12 Amps. But seriously, you shouldn't be using an extension cord. Buy the Wall Charger.

 

[nate704]

electrical fire is very dangerous that you don't want to experience. Improperly used wires and connection can burn the whole house down within minutes.

 

[ItsNotAboutTheMoney]

What is the distance from the outlet to the charge port,?

 

[BlipiIsPsycho]

The GFCI sounds like it's faulty to ewodrick's comment above. Replace the outlet and make sure the housing is properly installed and has all of the gaskets in place.

This shouldn't happen, the outlet should have tripped before it burnt the cord. Extension cords are used all of the time on power equipment drawing lots of amps on construction site. A Tesla Mobile charger will draw 12amps (really 11amps) on 120v. A 25ft 10ga extension cord can handle 20amps with no issues. Even at a 100ft, a 10ga extension cord can handle 20amp with a 4% drop in voltage. The issue most likely lies with the outlet and keeping the connection out of a standing puddle of water. Just my thoughts.

 

[ewoodrick]

The GFCI sounds like it's faulty to ewodrick's comment above. Replace the outlet and make sure the housing is properly installed and has all of the gaskets in place.

This shouldn't happen, the outlet should have tripped before it burnt the cord. Extension cords are used all of the time on power equipment drawing lots of amps on construction site. A Tesla Mobile charger will draw 12amps (really 11amps) on 120v. A 25ft 10ga extension cord can handle 20amps with no issues. Even at a 100ft, a 10ga extension cord can handle 20amp with a 4% drop in voltage. The issue most likely lies with the outlet and keeping the connection out of a standing puddle of water. Just my thoughts.

If I'm reading between the lines correctly, the cord isn't burning, it's an arc to the ground.

 

[BlipiIsPsycho]

If I'm reading between the lines correctly, the cord isn't burning, it's an arc to the ground.

You’re probably right, I just had the title in mind when I wrote my reply. The arcing still shouldn’t be happening without the GCFI tripping as you already noted. I was really responding after seeing comments about never using extension cords. When used correctly and the wiring is correct they should be safe in this scenario in terms of amperage and voltage. There is a bigger issue here with the electrical that may be dangerous even if an extension cord isn’t used.

 

[Tronguy]

Speaking as an engineer: If you've got char marks on the ground, then I agree with the other posters here that you likely had arcing between the cord and ground.

I'm making a bet that when you have the car charging, the junction between the plug of the Mobile Connector and the socket for your extension cord are lying on the ground. This is wrong on so many levels it's hard to count.

First off: water plus dirt or even water plus air pollution is a conductor. Maybe not a great conductor, but a conductor nonetheless. So, it's not just rain: Dew collecting around, or even high humidity, will allow 120 VAC to appear on edge of the plastic of the junction.

Next, if it's lying on the ground, well, there's a reason that people talk about grounding things: Ye Ground Is Very Conductive, no kidding. So, you get current flow.

It may start off slow, but, under these circumstances, there'll be heating, steam, degradation of the plastic, then plastic getting charred, and charred stuff conducts really well. Then you get what you saw. I agree that the GFCI should have gone off, maybe: But the GFCI is designed to detect when current is flowing on the ground wire in the cable. In your case, it's not flowing on the ground wire - it's flowing on the hot, straight into the Earth. So, I don't think your GFCI is actually faulty.

The solution is vaguely staring at you in the face. You'll note that that external house socket has a plastic cover on it. Further, said cover is not airtight. What that cover does is (a) keeps water from the driving rain or whatever from getting into the socket and (b) provides air flow enough to evaporate any concentration of dew or whatever that gets on the energized hardware in there. And there's long distances, electrically, between the electrical contacts of that socket and anything conductive. I don't know, but a half-bet says that the box that the socket is mounted inside of is plastic, and that would be with malice forethought.

So, going along these lines, I don't agree with the idea of wrapping up everything with tape. You're not going to make it airtight that way, so water molecules that get in there will stay there, preferentially, so you'll end up with an even more soaked connector. Now, the tape will keep the energized area inside from getting outside; but all that water in there, plus whatever atmospheric NOx/SOx or even CO2 (carbonic acid, anyone?) is going to corrode the metal in there, and that's not good.

What I would do: In the short term, putting a hook or something on the side of your house, like what people use for garden hoses, and hang the extension cord/end of the Mobile Connector so it's in mid-air, preferably with the junction level. Putting a little down-pointing micro-roof over it would be a plus. And making the hook plastic would be even better. And make sure that if water hits the side of your house during the rain, water doesn't flow into the blame junction.

In the long term: Quit screwing around and get a Wall Connector or similar from some other manufacturer installed. Those things are outdoor rated and have Zero problems with rain, sleet, snow, and ice. It'll cost you on the order of $1000; consider it part of the cost of having a BEV. Most places and, with the Fed, you get, I think, to deduct 30% of the cost on your taxes. Don't take my word on that last, check.

Finally: I've read the occasional post/story on the web where somebody takes apart a Mobile Connector to see what's in there. Interestingly, Tesla has Taken Steps about water. Some spots are very thoroughly sealed, other spots have no-kidding drain and vent holes. But running one in a puddle, or something that electrically looks like a puddle, is never a good idea.

 

[Jeff-4]

In the long term: Quit screwing around and get a Wall Connector or similar from some other manufacturer installed. Those things are outdoor rated and have Zero problems with rain, sleet, snow, and ice. It'll cost you on the order of $1000; consider it part of the cost of having a BEV. Most places and, with the Fed, you get, I think, to deduct 30% of the cost on your taxes. Don't take my word on that last, check.

A wired wall connector will also increase the value of your house, presuming you own it. Think about it, the LACK of a wall connector will reduce your home's attractiveness to buyers 10 years from now, all of whom will be driving EVs.

 

[KevinT3141]

But the GFCI is designed to detect when current is flowing on the ground wire in the cable. In your case, it's not flowing on the ground wire - it's flowing on the hot, straight into the Earth. So, I don't think your GFCI is actually faulty.

If something is arcing to the ground and the GFCI doesn't trip, then its definitely faulty. It actually ignores the ground wire, what it does is measure the difference in current between the hot and neutral wire. When all the current that goes out the hot comes back through the neutral (or the other direction, because you know, alternating current) there's no fault and no foul. When more goes out than comes back in, <click!>

 

[gregory.balan@]

I was under the impression using an extension cord is strongly advised not to do. I just had someone install an outlet closet and deleted the one that would reach

 

[MP3Mike]

Wrong gauge

How so? The outlet is probably only fed by 12 gauge, so a 10 gauge extension cord should be more than up to the task.

 

[Tronguy]

If something is arcing to the ground and the GFCI doesn't trip, then its definitely faulty. It actually ignores the ground wire, what it does is measure the difference in current between the hot and neutral wire. When all the current that goes out the hot comes back through the neutral (or the other direction, because you know, alternating current) there's no fault and no foul. When more goes out than comes back in, <click!>

I'm not sure of all this, but look at it this way:

1. Say you grab your handy 3-wire hair drier (hot, neutral, and safety ground wire) and turn it on. Current flows (more or less) from the hot to the neutral (the two blades on a standard 120 VAC socket), but no current flows on the safety ground. Ye GFCI does not trip because what it's looking for is current on the ground wire and there's none of that stuff.
2. Now, grab the 3-wire hair drier, on or off, and throw it into a full bathtub. Everything gets connected to everything (more or less) and current flows out of the hot and into both the neutral and ground. There'll be significant current on the ground wire, and the Ground Fault CI will detect that, pop open the connection at the socket for the hot and neutral (at least, I think it's just the hot and neutral, but it might be all three) and Saves The Day.
3. Next, consider a Standard House Connection. Down from ye power pole comes three wires: A hot, another hot 180 degrees out of phase, and a neutral. Note: No Ground. Then, as standard practice, the two hots and neutral go through the meter and, at the breaker box, the two hots go to the two hot bus bars and the neutral gets bolted to the neutral/ground bus bar. In Addition, A Big Green Wire gets bolted to that same neutral/ground bus bar, goes out of the house, and gets bolted, securely, to a no-kidding 6-foot copper ground stake that has been pounded into the physical ground. I've actually watched an electrician do this one year with a sledge hammer, starting off by standing on an a-frame ladder, and working the stake down until a couple of inches are left above grade. He then attached the copper wire from the breaker box to the ground stake with a thoroughly tightened clamp.

For what it's worth, all the houses in the area have their own ground stakes, giving the neutral up there on the power pole a kind of distributed connection to ground. Interestingly, despite dirt/gravel/rocks/soil/whatever, the actual resistance, measured with an ohmmeter, between ground stakes is down in the milliohms. What moist or dryish dirt loses by having relatively high resistance compared, say, to copper, it makes up by having the biggest cross-sectional area you've ever seen, and that makes R very, very low in R = resistivity_of_a_conductor/(area of said conductor).​

Now, consider the OP. There's moisture in the junction between the Mobile Connector and the extension cord. For fun, I'm going to claim that the Hot blade is closest to the physical ground (as in, dirt/soil/asphalt), and any moisture between the hot blade and the ground pin is either blocked or evaporated. Let there develop a current between the hot blade, through the ground, through the multitudinous ground stakes in the neighborhood (low resistance) and into the neutral/ground bus bar, and there's your circuit, leading back to city power.

So, yeah, if one gets a case of everything hooked to everything, then the ground wire would conduct, too - but it's not a tub of water where that's guaranteed. Instead, it's hot to (physical) ground, but not hot to the electrical ground wire. If there's no current (or very little current) on the electrical ground wire, the GFCI won't trip.

Now, if somebody stands up and says that a GFCI, besides checking for current on the ground wire, checks to make sure that the current on the hot and neutral are equal, then I take it all back.