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I think he is just saying the gross difference (120-80 = 40 vs: 60-40 = 20) may seem like a larger difference to some folks (OMG, that's 40 less than expected!, that must be bad!), while some folks will recognize that 40/120 and 20/60 are the same thing, and not sweat the gross magnitude, just focusing on the relative difference.
 

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Okay, that's the explanation, then. Too bad, because the car sure felt smooth at 75.
I have to add, just for general curiosity's sake mind you, that it also feels smooth at 96, which is the upper limit of the cruise control. Just saying...
 
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Interesting, thanks. Makes sense. But can you explain how doubling the distance magnifies the difference? I drive 60 miles (or more) on a charge around town. Equivalent to 120 miles on two charges. On the freeway, I'm going 40 miles on one charge. The difference is just 60 vs 40, no? Little regen, lots of wind resistance, lots of energy to maintain high speed. 60 vs 40 miles per charge or 120 vs 80 mpge. Or is it more complicated than that?

Also, my intuition has always been that driving in L wouldn't make much sense on the freeway, and might actually hurt mileage. Any thoughts about that? I rarely use L anymore and just use the paddle regen on the steering wheel to slow the car.
Yes, MikeBCo has it right, the magnifying effect is based on the familiarity one has with the units. A 40 mile difference between the range at a slow speed and at a fast speed becomes an 80 mile difference when translated into "per fuel unit" numbers, and that, to some, makes it "feel" bigger. A car rated at 15 mpg might see the same range mileage numbers as 17-18 mpg around town, normally 16 on trips like this, and only 13 mpg on this trip. Does a 13-17 mpg variation really "feel" as much as an 88-125 mpg variation?

As for regen levels... remember regen is created when braking, L and D are not driving gears. Your battery’s full charge holds a fixed amount of power. On level terrain, you use that full charge for acceleration and for maintaining speed. Maximum range is achieved by maximizing the portion of the full charge used for maintaining speed. Each time you accelerate, you increase the "acceleration" portion and reduce the "maintaining speed" portion.

Regenerative braking enables you to recapture some energy previously used for acceleration as you slow down, but when you accelerate back up to speed, you use more energy than you just recaptured. The impact of regen creation is that it reduces the "average amount of power" used per acceleration episode. A nice benefit in stop and go traffic. Nevertheless, each slow down/speed back up acceleration episode still increases the portion of the full charge you use for acceleration and reduces the portion you use for maintaining speed (i.e., for achieving range), but not by as much as it would if you had no regenerative brakes.

Seems to me the best choice of regen level to use, whether D or L and/or paddle, is the level that you as driver find best for controlling the speed of your car... you want to develop braking habits that minimize the amount of speed lost when traffic conditions require you to slow down. By doing so, you also minimize the additional quantity of power needed to "accelerate back up to speed." The higher the level of regen you apply (e.g., L vs D), the faster the car slows down, but the actual quantity of regen you create is related to the amount of speed you lose, not to how fast you lose it. The goal should be to minimize, not maximize, the quantity of regen created (minimize the amount of speed loss) in order to maximize the amount of the full charge you can use to maintain your speed (to add range).

Some find "one-pedal" driving in L enables them to develop efficient braking habits (even on the freeway where much of the driving is done using cruise control, where it is the computer, and not the driver, who is control of when the chosen D or L is applied to maintain speed). Others prefer to use D on the highway, and to use L in stop and go traffic and/or when using cruise control while headed downhill.
 

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If you must use an extension cord, use an J1772 EV extension cord. 120AC to level 1, level 1 to level 2 extension cord (female to male), to vehicle charge port.

Your local fire department, will thank you.
 

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If you must use an extension cord, use an J1772 EV extension cord. 120AC to level 1, level 1 to level 2 extension cord (female to male), to vehicle charge port.

Your local fire department, will thank you.
Learned something new, I didn't know these existed. Plug your 120V EVSE handle into one end, plug the other end into the car. Pricey at $190 for 20 feet. Basically a charge port on one end, charge handle on the other.

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Learned something new, I didn't know these existed. Plug your 120V EVSE handle into one end, plug the other end into the car. Pricey at $190 for 20 feet. Basically a charge port on one end, charge handle on the other.
Looks like a good way to have a charger in the garage and have it also able to be used outside safely (going through the wall instead of under the door).

-Charlie
 

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I have to add, just for general curiosity's sake mind you, that it also feels smooth at 96, which is the upper limit of the cruise control. Just saying...
Will second that. A few months back after having my GEN 1 for a bit but never much on the expressway I had to go to Novi MI, about 45 miles from home. But to get there I was on the Michigan equivalent of the Autobahn. I-96. I was going 90-95 and was amazed how well the Volt kept up. And, yes at that speed I was passed a few times. That stretch of road is insane, many many folks drive it everyday. The Volt handled very well.
 

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If you must use an extension cord, use an J1772 EV extension cord. 120AC to level 1, level 1 to level 2 extension cord (female to male), to vehicle charge port.

Your local fire department, will thank you.
I'm not so sure about that. The factory-supplied EVSE cord is only 16ga, and at 25' and 12A, it's at safe capacity.

Consult an electrician. I don't understand where all this talk of 12 and 10ga cords is coming from. 12ga is 20A cord, and 10ga is 30A. Any quality outdoor/HD rated 14/3 extension cord is more than adequate up to 50'. 12A is the rated continuous duty of a 120V/15A circuit/outlet (80% is the standard). As was mentioned earlier, any problems will be with the connections. If they're good, then it's all good. Check them often, and replace as necessary. For nearly 2 years, my wife charged at work on a 14/3 x 50' extension at 12A, 5 days a week, before L2 EVSE's were installed. We did the same at home for months before I installed a 240V/40A panel near the carport. Never any issues. Now, and for 5 years since, an aftermarket portable EVSE is located at the carport, and is supplied by 30' of 12/3, buried in conduit, charging at 240V/16A. All of the AWG and V/A ratings above are within NEMA standards, and considered safe in any reasonable environment (where humans live/work). All the cautions and warnings accompanying the EVSE and owner's manual are due to unknowns the MFG's can't control, such as what you're plugging into. The EVSE will protect itself. It won't protect what you're plugging into.
 

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The reason for specifying 12 or 10 is that "good quality heavy duty" are undefinable terms and people almost never specify the length they're dealing with, etc. At 14 gauge, if you start dealing with 50 or 100 foot cords, or lose whatever quality "heavy duty" happens to be, or the cord isn't new, or or or or... then 14 can be not enough and lead to EVSEs tripping or resetting, charges quitting in the middle due to low voltage, old cords heating up and potentially becoming hazards. 12 guage conductors are probably still fine becase they HAVE the margin. So when people pop up and say "what kind of extension cord is good enough" we say "12/3 rated for outdoor" and we're done. The difference in cost between 12 and 14 is about $0.25 a foot; it's not exactly a splurge.
 

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So when people pop up and say "what kind of extension cord is good enough" we say "12/3 rated for outdoor" and we're done. The difference in cost between 12 and 14 is about $0.25 a foot; it's not exactly a splurge.
I would agree. Also, the 12/3 should have a heavier duty (read: higher tension) plug that is hopefully less likely to have resistance/heating issues.

-Charlie
 

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Looks like a good way to have a charger in the garage and have it also able to be used outside safely (going through the wall instead of under the door).

-Charlie
My wall outlet is inside but I park and charge the Volt outside (garage is filled with '79 TR7 and '88 Tercel Wagon 4X4 both being restored). I run the charge cord under the door but have 1x3 strips of wood under it (the door opener is set so it doesn't reverse thinking the wood is an obstruction. The charge cord is not compressed in any way.
 

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'88 Tercel Wagon 4X4
I have an '89 Camry Alltrac with a manual trans, swapped with a 3s-gte engine and a bunch of other go-fast parts... also sitting in the garage. Rust free and doesn't need much other than a paint job due to failing clearcoat. I try to drive it at least once a week, though it hasn't happened much since covid started.

-Charlie
 

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I see that the OP ultimately didn’t need the extension cord but I’d like to suggest another potential issue with using 12A in that proposed scenario.

The Volt’s portable EVSE has a temperature sensor molded into the plug in case the outlet can’t handle 12A and gets hot enough to melt. With a drop cord that sensor will have no idea what’s going on at the wall outlet. For anyone using a drop cord at an outlet where they aren’t sure it can handle 12A, I’d strongly suggest checking the temperature frequently until you are confident that it isn’t overheating. I’ve melted a GFCI in the garage at 12A even with all the protections. There is a good reason it defaults to 8A on 120v.
 

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The Volt’s portable EVSE has a temperature sensor molded into the plug in case the outlet can’t handle 12A and gets hot enough to melt. With a drop cord that sensor will have no idea what’s going on at the wall outlet.
Any idea how that might work? There's plenty of images showing various EVSEs open out there and I've never seen one with anything other than the black, white, and green wires coming from the wall end. Is it a fusible link or something?
 

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Any idea how that might work? There's plenty of images showing various EVSEs open out there and I've never seen one with anything other than the black, white, and green wires coming from the wall end. Is it a fusible link or something?
I should have said that the latest version has that but I presume some others do too, especially after the recall of the earliest Gen1 portable EVSE. The Bolt/Volt portable EVSE with the ClipperCreek Gen2 board has wires running to two extra contacts on the control board PCB. Those same connections are unpopulated in the AmazingE EVSE with the exact same board:

They are labeled “Therm1 In” and “Therm 2 In Gnd”

According to ai4px on our sister forum, it should have a thermistor embedded in the plug that reads 100k Ω at 25C (77F). The firmware on the AmazingE EVSE seems to ignore this, at least for 240v.


I’m not sure which EVSE you’re looking at but I know the earliest Gen1 Voltec EVSE’s were recalled for melting. I assumed the replacements had the thermistor but there have been a few models and I don’t know if they all do. My understanding is that they only care about it for 12A 120v charging so you probably won’t find it in a Euro version.
 
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