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Can someone tell me how long it will take my 2018 Volt to charge from empty to full if I use 240volts (with appropriate adapter) and my OEM EVSE? It takes about 12 hours using 110 volts. Also, if I do use 240 volts, does anyone know how many amps it will draw? 16????

I ask this because I have read several of the threads on how to do be this and it seems to me it will be very easy to use my unused clothes dryer recepticle. I will buy a new dryer cord, which is color coded and connect each hot (120v) to a side of hospital grade RED 120v 20amp outlet. And of course connect dryer ground to the RED outlet ground. Am I missing something here???
 

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I ask this because I have read several of the threads on how to do be this and it seems to me it will be very easy to use my unused clothes dryer recepticle. I will buy a new dryer cord, which is color coded and connect each hot (120v) to a side of hospital grade RED 120v 20amp outlet. And of course connect dryer ground to the RED outlet ground. Am I missing something here???
Make sure the breaker is sized to 20A as well.
 

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Can someone tell me how long it will take my 2018 Volt to charge from empty to full if I use 240volts (with appropriate adapter) and my OEM EVSE? It takes about 12 hours using 110 volts. Also, if I do use 240 volts, does anyone know how many amps it will draw? 16????
I'm pretty sure the OEM EVSE only ever offer up to 12 amps, regardless of voltage. So at the same amps, and twice the voltage, it'll take about half the time.
 

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Can someone tell me how long it will take my 2018 Volt to charge from empty to full if I use 240volts (with appropriate adapter) and my OEM EVSE? It takes about 12 hours using 110 volts. Also, if I do use 240 volts, does anyone know how many amps it will draw? 16????

I ask this because I have read several of the threads on how to do be this and it seems to me it will be very easy to use my unused clothes dryer recepticle. I will buy a new dryer cord, which is color coded and connect each hot (120v) to a side of hospital grade RED 120v 20amp outlet. And of course connect dryer ground to the RED outlet ground. Am I missing something here???
My 2018 Volt charges in 4 1/2 hours with level 2 charging. That's @240VAC and 16 amps.
 

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If you go into your charging menu in your 2018 Chevy Volt you will find the ability to change the charging current from 8 amps to 12 amps. When I charge with my level 2 charger it automatically charges at the 12 amp level. Level 2 charging is 24 amps total, 12 amps on each 120VAC line. I confirmed this by measurement.
I know you said you measured it at 12 amps each line for a total of 24 amps. But, it was my understanding that 16 amps is the MAX the onboard charger will allow. As far as I know, I am charging my 2018 at 16 amps and it also takes 4.5 hours.
Can anyone confirm if the onboard charger on a 2018 will charge at 24 amps?
 

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If you go into your charging menu in your 2018 Chevy Volt you will find the ability to change the charging current from 8 amps to 12 amps. When I charge with my level 2 charger it automatically charges at the 12 amp level. Level 2 charging is 24 amps total, 12 amps on each 120VAC line. I confirmed this by measurement.
With 240V power, the current flow is between the two hot lines. If there is 12 amps flowing in one line, it is the same 12 amps you measure in the other. It isn't doubled. Your power transfer is doubled by going from 120 to 240 and if you use a legitimate L2 EVSE, the Gen2 (except '19) allows 16 amps instead of 12., and that current increase is why it's not 6 hrs -- 12hrs x (120 /240) x (12/16) = 4.5 hrs.
 

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I know you said you measured it at 12 amps each line for a total of 24 amps. But, it was my understanding that 16 amps is the MAX the onboard charger will allow. As far as I know, I am charging my 2018 at 16 amps and it also takes 4.5 hours.
Can anyone confirm if the onboard charger on a 2018 will charge at 24 amps?
You are correct in your understanding. The arithmetic is in post #9.
 

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With 240V power, the current flow is between the two hot lines. If there is 12 amps flowing in one line, it is the same 12 amps you measure in the other. It isn't doubled. Your power transfer is doubled by going from 120 to 240 and if you use a legitimate L2 EVSE, the Gen2 (except '19) allows 16 amps instead of 12., and that current increase is why it's not 6 hrs -- 12hrs x (120 /240) x (12/16) = 4.5 hrs.
In the quote you provided did I say the current is doubled? No I did not.
240VAC in reference to neutral is two 120VAC independent lines that are spilt phase 180 degrees apart. With respect to neutral, each 120VAC lines are considered independent circuits. These two individual 120VAC lines with respect to neutral are capable of supplying independent current from each. When I'm measuring the current on one of the 120VAC lines it is an independent circuit capable of delivering a current independent of the other 120VAC circuit that's 180 degrees out of phase from the other. (120VACx12AMP)×2= 2,880 watts.

If I'm measuring 12 amps, and not 16 amps, then how am I charging in 4.5 hours? Why not 6 hours?
 

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In the quote you provided did I say the current is doubled? No I did not.
What you said was "Level 2 charging is 24 amps total, 12 amps on each 120VAC line." That is doubling the actual current that flows from one hot wire to the other hot wire. There is no neutral. In fact, as an example, there isn't even a neutral wire in a NEMA 10-30 outlet. There are NOT two independent circuits.

These two individual 120VAC lines with respect to neutral are capable of supplying independent current from each. When I'm measuring the current on one of the 120VAC lines it is an independent circuit capable of delivering a current independent of the other 120VAC circuit that's 180 degrees out of phase from the other. (120VACx12AMP)×2= 2,880 watts.
That is incorrect. If either hot wire is disconnected, no current will flow. And 2880 watts for 4.5 hrs would only be putting 11.7kWh into your battery at 90% efficiency. You have a larger usable battery than that. You even said something to the effect that the numbers don't add up.

If I'm measuring 12 amps, and not 16 amps, then how am I charging in 4.5 hours? Why not 6 hours?
Unless you are using the OEM EVSE (which limits current to 12A regardless of voltage) with an adapter on a 240V outlet, or have a rare EVSE that allows you to select 12A as a max current, I can't even imagine such a measurement. Your 2018 will never limit you to 12A on a normal L2 EVSE. What kind of meter are you using the measure the current? Gen1 Volts on an L2 EVSE charge at 3.3kW, and Gen2 at 3.84kW I believe (except 2019). That is 240 V x 16A.
 

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Electrical Engineer here. Level 2 charging using a stock EVSE is still at 12A, but the benefits are from doubling the voltage (120 to 240) which gives you a faster charge.

I’d love to have “fast” charging with my Gen 1, but will settle at 8.5-9 hours for now.

For those who can do it, it’s a great idea if you have another EVSE dedicated to portable use such as in your car.
 

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I believe that GM, in an abundance of precaution, limited the EVSE they supplied with the car to a maximum of 12 Amps, not knowing how well the house circuits were installed. The on-board Charger will handle currents up to 16 Amps and commercial charging stations are generally capable of supplying such current safely (as is also the case for correctly built house circuits with the properly sized wiring and outlets having wire wraps on the sides of the outlet, not with wiring bayoneted to the back of the outlet). Most, if not all, third party EVSEs can supply16 Amps or more. A handshake between the on-board Charger and the connected EVSE notifies the car of the current capability of the EVSE. The car can then make calculations to show the length of time of the charge. Please correct me if I have misstated anything.
 
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oem EVSE
gen 1 and 2 EVSE-- 8/12 amps on 120v
gen 2 EVSE-- 12 amps on 240v

aftermarket
the car charger will allow 15 amps but the EVSE has to tell it to do it. the oem EVSE limits it to 12 amps

the reason they keep it at 12 amps at 120 volts is becouse a 15 amp breaker thats in everyone house is limited to 12 amps by code
further reducing it to 8 amps if you have something else sharing the breaker with your car

12+ hours on 120v oem
5.5 hours on 240v oem
15 amp little over 4 hrs
 

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In the quote you provided did I say the current is doubled? No I did not.
Umm, that is literally exactly what you said: "Level 2 charging is 24 amps total, 12 amps on each 120VAC line"

The two 120 V A/C lines don't run at 12 amps each. When you measure one wire against the other, the total amperage is 12, not 24.

Watts = volts x amps

Therefore, if you simply double the voltage, you double the watts.

Energy transferred = watts x time (usually expressed as kilowatt hours).

So, if you double the voltage and leave the amperage the same, the amount of time it will take to transfer a given amount of energy (such as that required to charge the Volt's battery) will be halved.

My understanding is that this is exactly what happens if you use the OEM EVSE plugged into 240V instead of 120V. It will take 6 hr to give the Volt a full charge - half the 12 hr it takes at 120 V/12 amps. The Volt is capable of charging at 16 amps but the OEM EVSE is limited to 12 amps. So charging with an aftermarket 240 V EVSE results in faster charging (4.5 hr) because those EVSEs can charge at 16 amps.

12+ hours on 120v oem
4.5 hours on 240v oem
16 amp ?
It should be ~6 hr on the oem evse at 240 V and 12 amps, and it is a bit more than 4 hr on an aftermarket level 2 evse at 240 V and 16 amps
 

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Roughly 5 and a half hours.
 
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