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Using an Extension Cord With The FFE

Posted: Fri Mar 31, 2017 9:02 pm
by marcham93
Hello, all!

I just signed the papers on a 2017 FFE lease and I'm super excited. I have a few questions for those of you knowledgable owners out there. Right now I have a 120v outlet outside by the garage, but the issue is that the included 18 foot cord wouldn't reach.

Would I be able to use a heavy duty 10 gauge extension wire to make it out to the driveway? I know that extension cords aren't recommended, but if I use one that could handle the power would that be fine?

Thanks for the advice, all.

Re: Using an Extension Cord With The FFE

Posted: Fri Mar 31, 2017 11:07 pm
by NightHawk
Depends on the length you need I guess, but I have used about a 10foot 12ga extension cord successfully with the Ford 120v charging unit on my 2014 FFE many times away from home.

Re: Using an Extension Cord With The FFE

Posted: Sat Apr 01, 2017 9:41 am
by marcham93
Seems to be a sensitive topic with some and a 'no big deal' conversation with others.

Most people seem to do fine with a good extension cord, so I'm hoping I won't run into any trouble with a heavy duty cord.

I assume that Ford discourages against it to prevent people from using old extension cords they have laying around.

Re: Using an Extension Cord With The FFE

Posted: Sat Apr 01, 2017 10:51 am
by henryfocus
Completely unscientific evidence here: I had a situation once where I needed to charge with a 50ft rather thin extension cord otherwise I wasn't going anywhere. The cord became significantly warm to the touch. Luckily it was a cold out.

Re: Using an Extension Cord With The FFE

Posted: Sat Apr 01, 2017 8:18 pm
by michael
It will absolutely work if the cord is properly rated for the current drawn.

The reason manufacturers always say not to use an extension cord is because you are not supposed to do so. Article 625 of the NEC sets a maximum distance of 12" for the cord from the outlet to the EVSE protective equipment.

This doesn't mean it wont work. It just means you are not supposed to do so. The electrons don't care.

Re: Using an Extension Cord With The FFE

Posted: Sat Apr 01, 2017 8:47 pm
by marcham93
michael wrote:The reason manufacturers always say not to use an extension cord is because you are not supposed to do so. Article 625 of the NEC sets a maximum distance of 12" for the cord from the outlet to the EVSE protective equipment.
Ah, it is a law. Interesting to see the source of the warning.

I figured I'd be safe as long as the cable was properly rated.

P.S. - What do you guys think of this cable from Goodyear? It seems like it would be excellent for what I need; easily retractable to the end of the driveway and back if needed. It is heavy duty rated 12 gauge and designed for commercial and industrial use.

https://www.amazon.com/gp/product/B01GF ... PDKIKX0DER

Re: Using an Extension Cord With The FFE

Posted: Sat Apr 01, 2017 10:08 pm
by NightHawk
marcham93 wrote:
michael wrote:The reason manufacturers always say not to use an extension cord is because you are not supposed to do so. Article 625 of the NEC sets a maximum distance of 12" for the cord from the outlet to the EVSE protective equipment.
Ah, it is a law. Interesting to see the source of the warning.

I figured I'd be safe as long as the cable was properly rated.

P.S. - What do you guys think of this cable from Goodyear? It seems like it would be excellent for what I need; easily retractable to the end of the driveway and back if needed. It is heavy duty rated 12 gauge and designed for commercial and industrial use.

https://www.amazon.com/gp/product/B01GF ... PDKIKX0DER
That listing says "40 ft, 14AWG"
40ft might be pushing it, I'd recommend the smallest length that will work for you and 12AWG would be better.

Here is one that works for me, I use a separate cord reel with it:
https://www.amazon.com/gp/product/B002H ... UTF8&psc=1

Re: Using an Extension Cord With The FFE

Posted: Sat Apr 01, 2017 10:13 pm
by marcham93
Awesome, thanks. I saw that one before and it would be perfect. Like you said, I can always purchase the reel separately. :)

UPDATE: Just to keep you guys updated on my research. It seems that a cord of around 20-feet pulling up to 16 amps should be 8-guage. As a result, I think I will be going with this cable linked below. I want to play it safe and this seems to be the best option.

https://www.amazon.com/Gauge-Welding-Ex ... 06W563YSZ/

Source: http://www.amplepower.com/primer/gauge/

Re: Using an Extension Cord With The FFE

Posted: Sun Apr 02, 2017 8:36 pm
by EVA
The one you linked to at Amazon is pretty similar to the one I carry in my Tesla - have used it many times at hotels and other 120V outlets to charge the car overnight. You got the kind of overkill gauge to be safe.

This is the one I used - I liked the yellow wire and the lighted ends.

https://www.amazon.com/gp/product/B00004SQF1/

The one you linked to is 8 gauge, and is slightly cheaper than the one I use at 10 gauge. The only downside to the heavier gauge, it might not bend as easily and will be heavier.

As an aside, Tesla's charging circuit is really critical of the power. It will reduce amperage and stop charging if it senses any slight changes. I've never had a problem with the extension cord and reduced amperage or turning off charging the car.

Re: Using an Extension Cord With The FFE

Posted: Mon Apr 03, 2017 1:08 pm
by triangles
Using an extension cord can be safe and it can be a fire hazard. If the ends of the cord become dirty or corroded they will have resistance which will generate heat. The higher the current and/or resistance the higher the heat. If you want to get technical about the ampacity of the wire you intend to use Ugly's Electrical Reference is a great reference with a lot of no BS info to help you determine what gauge extension wire will be safe for your situation. I provided a link to amazon but I think some of the big box hardware stores like home depot carry it too. I realize it's not directly applicable to an extension cord with the FFE but when I used to work with industrial equipment we had to pull the coiled power cords out of their box for the servo motors while testing/debugging. If we didn't the powers cords would over heat, melt, and short out. While not likely, I do think it would be possible to have a scenario where an extension cord coiled/balled up and enclosed such that it cannot transfer heat to the surrounding air could get hot enough to melt.

Probably the best thing you can do to avoid a problem with an extension cord is to not use one. If that's not an option, this is a place where you want to spend more money for a quality cord and get the lowest gauge (thickest, 10ga min.) wire you can. Don't buy a cord any longer than you absolutely need. To be extra safe feel the cord near the ends after plugging in. If they quickly become hot, unplug from the car asap and don't use that cord. You probably should also periodically check the cord for heat while charging. It's not unusual for the cord to become warm just make sure it doesn't get hot. Yes I know that last part is vague but this is where you have to use your grey matter to decide what is and what isn't acceptable when you are using your laser precision temperature measurement devices at the end of your arms <sarcasm> Suffice it to say, slightly warm = ok and hot = bad!

From my personal experiences about a year ago, I used the book mentioned above as a guide to determine kind of extension cord I needed. I determined a 10ga 40' extension cord would be safe for me. I don't remember the exact details but I think a 12ga would have been sufficient but I went a size or two thicker than what I needed for an added margin of safety. I've only used it a hand full of times and have had no issues. I've never need anywhere near the full 40' but made sure the coiled up remaining wire was spread out enough to dissipate heat should it get hot. As an added safe guard and since charging time wasn't an issue, I set my EVSE to charge at 8A instead of 12A that the included Ford EVSE will pull. Oh yeah, In case you're wondering, you won't find a cord rated higher than 15A even though the wires inside may be capable of higher current simply because the connectors on the ends are only rated at 15A and also the outlets are 15A max as well.

I can tell you from experience to avoid the Harbor Freight cheapies unless you want to start a fire. I had an old cord of unknown gauge that I got from harbor freight years ago. I didn't expect it to work but I wanted to experiment and see what would happen. It was a short experiment as almost immediately the cord near the ends became too hot to touch. Had I been stupid enough to try a full charge, I likely would have burned down my house. This is why they don't want you to use an extension cord since inevitably some idiot would burn their house down and blame Ford for their own stupidity.