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extension cord?

NJ_JL 2020

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Anyone using extension chords for charging? I know about the voltage drop and how this will draw more current, and that typical cheaper cords are thinner and not rated for high currents. Before digging into this I did charge with a 50' cord, and have since stopped using this. Its a bit tight but manageable.

Anyone else using cords? it helps when my other cars are in the garage and the jeep is in the driveway.

Thanks.
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NJ_JL 2020

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Thx. Looking at options now.
 

DonH63

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Just get one the proper size and make sure connections are good, not corroded or loose. House wiring these days is usually 14 AWG for 15-A runs (vast majority), 12 AWG for 20-A runs, so a 50' cord 14 AWG or larger (12 or 10 AWG) should be fine. I've been using a 50', 14 AWG outdoor cord on my charger and compressor for years. Do not get a small 18 or 16 AWG cord.
 

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Just get one the proper size and make sure connections are good, not corroded or loose. House wiring these days is usually 14 AWG for 15-A runs (vast majority), 12 AWG for 20-A runs, so a 50' cord 14 AWG or larger (12 or 10 AWG) should be fine. I've been using a 50', 14 AWG outdoor cord on my charger and compressor for years. Do not get a small 18 or 16 AWG cord.

Thanks, this is the info I was looking for!!
 

driventoadventure

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Just get one the proper size and make sure connections are good, not corroded or loose. House wiring these days is usually 14 AWG for 15-A runs (vast majority), 12 AWG for 20-A runs, so a 50' cord 14 AWG or larger (12 or 10 AWG) should be fine. I've been using a 50', 14 AWG outdoor cord on my charger and compressor for years. Do not get a small 18 or 16 AWG cord.
This is the right answer. Voltage drop is a function of resistance which is governed by the wire gauge (and load, but given a static load, the gauge is the factor we care about for this example). Get yourself a good 12AWG extension cable and your voltage drop across the extension at 15 amps will only be about 2.6v, or about 2%. That's well within the capabilities of the cord to dissipate heat, and the charger/circuit to manage load. If you're really worried, drop your charging to 12 amps, and your less likely to be on the max continuous load of your circuit breaker. (Those numbers are for 50 feet, the numbers basically double for 100ft, but still will be reasonable enough if you limit the current to say 12a. I wouldn't do 100ft with 12awg, but it's not likely to result in fire as long as the cord remains pristine.) If you are REALLY worried, you can get a 10awg from Home Depot - $130 for 50ft and $170 for 100ft. Then you're somewhere around 1% loss, and your in-wall wiring becomes the issue. Don't forget that your in-wall circuit length needs to be calculated.

As Per Owners Handbook
IMG_20240611_101209.jpg
It only states this for liability reasons. People don't know how electricity works. They will just get a 50ft extension that's 16 AWG and run it at full 15a load, not realizing that the drop is significant enough to be an issue - a ~6v droop at 15a results in 90watts of heat generated on the cable and can potentially be enough to cause melting or fire and will almost certainly result in failure.

Also, even experts sometimes forget that the in-wall wiring is likely only 12awg and your length really needs to account for that in-wall length, so depending on where the extension is, that could be adding another 20ft to the circuit.
 
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ras815

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I would strongly consider first: is that a risk you really want to take at your home?
 

alphawolff

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Just a heads up, if you use an extension cord you will almost certainly get a service charging system light from time to time. The jeep monitors amperage input and if it drops (or spikes) unexpectedly it will stop charging and sometimes prevent charging until the code is cleared.

When using a level 1 charger this is a *very* common issue, especially if the house's wiring is older. My house built in 1942 was an absolute crapshoot if it managed to charge overnight. An extension cord will have roughly the same effect, but also amplifying the issue if your home wiring isn't up to snuff.

Get a proper 8-10 gauge extension cord and you won't have any fire issues or anything like that, but don't be surprised if you go out in the morning and it's not charged like you expected it to be.
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