Correct J-1772 Extension cord

ZuleMME

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Here, this table is better, these cables are 105degree rated, ironically the values might be lower due to being in a casing with other cables. But you get the idea. Always choose the thicker (lower awg) cable.

Ford Mustang Mach-E Correct J-1772 Extension cord 0212ad021265e86c7c5f96fc9f2d3c14eba8c6de
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RedDragon

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Here, this table is better, these cables are 105degree rated, ironically the values might be lower due to being in a casing with other cables. But you get the idea. Always choose the thicker (lower awg) cable.

0212ad021265e86c7c5f96fc9f2d3c14eba8c6de.png
and the values below the 105 C, for instance, are the Amps that can go through?
 

ZuleMME

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and the values below the 105 C, for instance, are the Amps that can go through?
Yes, but keep in mind those are non continuous ratings. You'd want to never pass 80% of that over 3 hours of use.
 

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Interesting that has the same pics as what @RedDragon posted above. I wonder if it really is the same gauge wires? Can you take a pic of the actual writing on the cable? So far I'd recommend the lectron's 2x8awg and 1x10awg over a 3x10awg...
Will do. Give me a bit of time - crazy end of year work stuff
 

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The 80% ampacity rule is one of the most misunderstood things in the NEC. The first thing to keep in mind is that the NEC only applies to premesis wiring. Anything past the outlet is utilization equipment to which the NEC does not apply.
For such equipment, the manufacturer‘s instructions are the key. If the manufacturer doesn't state that derating is required for continuous use, it’s not required.
The other thing to keep in mind when buying electrical equipment is to be sure it is listed to a safety standard by a nationally-recognized testing lab such as UL or ETL.
 


EELinneman

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Here is a close up of the cable and the connectors on the extension I bought.
Ford Mustang Mach-E Correct J-1772 Extension cord MME Cable
Ford Mustang Mach-E Correct J-1772 Extension cord MME Connectors
 
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RedDragon

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Here is a close up of the cable and the connectors on the extension I bought.
MME Cable.jpg
MME Connectors.jpg
Thanks!

So for all those who are educated on the topic out there, it looks like the Lectron with its 2x8awg, 1x10awg, and 1x16awg should actually be able to handle more amps than this as its 3x10awg and 1x18awg, correct?

If thats the case, then why is lectron rated 40A with higher gauge as opposed to this one with a 50A rating with lower overall wire gauge? Is there something else at play?
 

ZuleMME

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Dumb question maybe. Couldn't you just buy a NEMA 14-50 extension cord, with at least 8 gauge wire? Like this: https://www.amazon.com/Mophorn-Durable-Premium-Extension-Motorhome/dp/B06X9NGN23/

Is there a reason we should extend the J1772 cord versus the power cord?
6 in one hand half dozen in the other. Literally the power is 240v AC with 2 hots, a neutral and a ground. J1772 will eliminate the neutral and give you 2 hots (the thick cables), a ground (the middle gauge cable), and 2 pilot signals (tiny wires are fine). The question is do you want to move the EVSE down further or have it further away. No right or wrong answer.

I believe these extensions skip the proximity pilot. But interestingly it still works on mine... So I dunno. The control pilot is certainly there as I can still control my charge rate from the EVSE also. Maybe that last 18awg is a 2 conductor pair...

Regardless that Inteset seems dangerous to list 40A only in the listing and 50A on the couplers. Perhaps those ratings are for the COUPLERS and not the cable. Go with the higher gauge (lower number) unless you need a different distance.
 

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If thats the case, then why is lectron rated 40A with higher gauge as opposed to this one with a 50A rating with lower overall wire gauge? Is there something else at play?
Maybe 50A is just the rating for the J1772 connector that they used.

Dumb question maybe. Couldn't you just buy a NEMA 14-50 extension cord, with at least 8 gauge wire? Like this: https://www.amazon.com/Mophorn-Durable-Premium-Extension-Motorhome/dp/B06X9NGN23/

Is there a reason we should extend the J1772 cord versus the power cord?
A J1772 is more versatile in that it can be used at a public charging station that's ICEd.
 
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RedDragon

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Dumb question maybe. Couldn't you just buy a NEMA 14-50 extension cord, with at least 8 gauge wire? Like this: https://www.amazon.com/Mophorn-Durable-Premium-Extension-Motorhome/dp/B06X9NGN23/

Is there a reason we should extend the J1772 cord versus the power cord?
for me its versatility. That cord
Dumb question maybe. Couldn't you just buy a NEMA 14-50 extension cord, with at least 8 gauge wire? Like this: https://www.amazon.com/Mophorn-Durable-Premium-Extension-Motorhome/dp/B06X9NGN23/

Is there a reason we should extend the J1772 cord versus the power cord?
For me its versatility:
- can use at public EVSE where access is tough or ICE'd
-if im charging through an outlet, could use it with either a standard outlet, 14-50, etc depending on mobile charger unit/outlet circuit

the 14-50 extension can ONLY be used on a 14-50 outlet.
 

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Thanks!

So for all those who are educated on the topic out there, it looks like the Lectron with its 2x8awg, 1x10awg, and 1x16awg should actually be able to handle more amps than this as its 3x10awg and 1x18awg, correct?

If thats the case, then why is lectron rated 40A with higher gauge as opposed to this one with a 50A rating with lower overall wire gauge? Is there something else at play?
There is. A wire’s ampacity is basically the current that the wire can handle without damaging its insulation. Thus a smaller wire with a higher temp rated insulation can be rated to safely carry more current than a larger wire with lesser insulation. Look at the internal wiring of a space heater - in many cases it will be much smaller than the cord because it has Teflon or other high-temp insulation.

having said that, there are many other factors that come into play that will ultimately determine the final safe ampacity. The device terminations are a big factor.
 
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RedDragon

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Well, technically it can support 40A charging with a 40A rating. It's not until you have it plugged in for more than 3 hours that de-rating for safety comes into play.

You're correct that a 40A extension cord would be fine for MOST L2 public charging stations, but not necessarily all. A 60A extension would cover the MME, but I've never seen one above 40A. This problem would completely go away if we could just reduce the power draw in the car, but Ford hasn't given us that ability. For now, all you can really do is get a 40A extension and not use it on stations that could supply more than 32A (or 40A for less than 3 hours).
Quick question here also - if Ford allowed us to change the amp draw when charging, you still couldnt use the Ford Mobile charger on a 30 amp dryer outlet b/c the mobile charger is "dumb" and would still attempt to draw 32 amps, correct? It wouldnt adjust to the car's new 24 amp charge setting, right?
 

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Quick question here also - if Ford allowed us to change the amp draw when charging, you still couldnt use the Ford Mobile charger on a 30 amp dryer outlet b/c the mobile charger is "dumb" and would still attempt to draw 32 amps, correct? It wouldnt adjust to the car's new 24 amp charge setting, right?
No, the EVSE doesn’t decide on its own how much power to draw. The EVSE and car communicate to determine the maximum amperage they both can handle.
 

ZuleMME

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No, the EVSE doesn’t decide on its own how much power to draw. The EVSE and car communicate to determine the maximum amperage they both can handle.
The EVSE most certainly DOES tell the car what maximum rate is supported via the pilot signal. But the car has the option to go lower if it needed to. Just not higher unless there was a serious problem. You can get a EVSE to support about any outlet configuration. Many a Tesla owner has plugged into outlets that don’t support over 30 amps at campgrounds and they lower the cars draw to compensate. We can’t do that, yet.

But the outlet and wiring should be protected by the circuit breaker thus it *should* be safe to try drawing more than is supported and thus the breaker would trip. But this is a liability can of worms if not installed right.
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