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Discussion Starter #1
OK, still tweaking this EVSE and saw some default vehicle details the EMW app is using and wondering if they are correct:

2018 Volt

Battery Capacity = 19.4 kWh
(would have expected this to be 18.4 kWh but maybe this is the total capacity not just the usable capacity?)

Charge Rate = 3.60 kW
(makes sense although the EVS routinely reports up to 3.78kW per their own app)

EVSE Efficiency = 92%
(no idea if this is accurate but EMW built the EVSE and they set the number so I'm leaving it alone)

Driving Range = 63 miles (app defaulted to 53 but right now I usually get 63 miles when fully charged so I changed this)

Also noticed the app usually underestimates how many miles of range the car has after being charged. For example, car is fully charged right now and it reports 60 miles of range while the EMW app reports 55 miles. I told the app I plugged in with 30 miles remaining.

Anybody have any thoughts on these settings?

Thanks
 

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I'm confused. Why do you need to change or setup anything? This should be a plug & play thing. My 240V EVSE setup was 1) hang on wall, 2) plug in to outlet. 3) Plug in to car.
 

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I'm confused. Why do you need to change or setup anything? This should be a plug & play thing. My 240V EVSE setup was 1) hang on wall, 2) plug in to outlet. 3) Plug in to car.
That's funny, that's all I did too! I did get a message from BC Hydro that I used 4 Kilowatt hours over same period last year. Well in that period I got a Volt and a second TV that's on all the time. At 8.9 cents a kilowatt hour, that's another 36 cents over last year. Maybe if I got a second EV they would owe me money! :p
 

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Discussion Starter #4
Thanks Steverino. The JuiceBox actually is pretty much plug and play but appears to be highly configurable too. Their user interface on the iphone app allows the user to modify charge settings as I mentioned. They ask you what model/year your car is and they preconfigure the charge settings for you based on the car.

I was merely reviewing their default settings and had some questions about the values that EMW chose for the 2018 Volt. For example, they defaulted the battery capacity to 19.4 kWh - I expected that they would have set that to 18.4. That's my question, why did they pick 19.4 instead of 18.4? Hope this makes sense. Thanks again.
 

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The car decides how much it can charge, the EVSE will not be asked by the Volt for more than the car can handle. The EVSE can't force feed the car, the car is in control.

The same EVSE that can feed my Bolt based on it's 7.2 kW capability will feed my Volt at 3. No programming needed. The car decides that. The only thing you could do is "starve" the amount available by putting a limiter on the EVSE.

But assuming your wiring can handle it, leave it at max and the car will take as much as it needs. You really don't need to do anything.

Why did your EVSE or app vendor use 19.4 kWh? No idea, ask them. The 2018 has 18.4 kWh battery with 14 kWh of that being useable. So refilling an empty battery will take 14 kWh plus a little extra for line loss.
 

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Discussion Starter #6 (Edited)
I totally get that the car governs how it gets charged of course - just was wondering if anyone else out there had a JuiceBox and knew why they configured it this way? I'm happy to pose this question to EMW along with an explanation of that EVSE efficiency parameter and report back if anyone is interested.

Like you mentioned, the Juicebox has also a setting for how much (or little) amperage the EVSE will make available to the car too. For example, the JuiceBox can be configured to deliver only 16 amps (it's capable of delivering up to 40 amps). Not sure why anyone would want to throttle back but it will let you. My EVSE is on a dedicated, 50-amp circuit (and my Volt of course can only accept a max of 16 amps) so l left that set to 40amps even though the car will never use more than 16. Thanks again!
 

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Not sure why anyone would want to throttle back but it will let you.

If your EVSE is capable of pulling more current than your electric circuit can handle, the Amp limiter is a safety feature. Pre-existing wiring may be fully adequate for a 2011 Volt but not a 2017 Bolt for example. :)

However, if the electric line is beefy enough to handle 40A (or more), then the amp limiter really does not matter.
 

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Why did your EVSE or app vendor use 19.4 kWh? No idea, ask them. The 2018 has 18.4 kWh battery with 14 kWh of that being useable. So refilling an empty battery will take 14 kWh plus a little extra for line loss.
5 kwh per day sucked up in losses, wifi connectivity, reporting analysis, and for sending all the spam when the highly-connected EVSE gets pwnd by Chinese hacker selling fake ginkgo pills? :)
 

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OK, still tweaking this EVSE and saw some default vehicle details the EMW app is using and wondering if they are correct:

2018 Volt

Battery Capacity = 19.4 kWh
(would have expected this to be 18.4 kWh but maybe this is the total capacity not just the usable capacity?)

Charge Rate = 3.60 kW
(makes sense although the EVS routinely reports up to 3.78kW per their own app)

EVSE Efficiency = 92%
(no idea if this is accurate but EMW built the EVSE and they set the number so I'm leaving it alone)

Driving Range = 63 miles (app defaulted to 53 but right now I usually get 63 miles when fully charged so I changed this)

Also noticed the app usually underestimates how many miles of range the car has after being charged. For example, car is fully charged right now and it reports 60 miles of range while the EMW app reports 55 miles. I told the app I plugged in with 30 miles remaining.

Anybody have any thoughts on these settings?

Thanks
For you purposes the battery capacity should be entered as 14.1 - 14.3 kWh. The total battery capacity is 18.4 but that is not relevant to its use and charging.

Level 2 charging at home for 3.6 kW: 230V @ 16 amp or 240V @ 15 amp

Level 1 charging efficiency estimated at ~83%, Level 2 charging efficiency estimated at ~87%

Driving range will vary. GM estimates 3.76 miles per kWh and ~14.1 kWh total battery capacity for a range of 53 miles.
 

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Discussion Starter #10
For you purposes the battery capacity should be entered as 14.1 - 14.3 kWh. The total battery capacity is 18.4 but that is not relevant to its use and charging.

Level 2 charging at home for 3.6 kW: 230V @ 16 amp or 240V @ 15 amp

Level 1 charging efficiency estimated at ~83%, Level 2 charging efficiency estimated at ~87%

Driving range will vary. GM estimates 3.76 miles per kWh and ~14.1 kWh total battery capacity for a range of 53 miles.
Awesome! Exactly what I was looking for, thank you! I will give the capacity and efficiency numbers a try and see if it brings the app's range estimate more in line with the Volt's GOM estimate.
 

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Per the information about the Lear 3.3kW high voltage battery charger used on a
number of major automotive manufacturer electric automobiles, most notably
the Chevrolet Volt

Efficiency: with 208 VAC input, the charger was calculated to be 91.7%
efficient while operating between 3.0-3.3 AC kW.

Charging at Level 1 with 120 VAC input the charger was calculated to be
90.6% efficient while operating near 1.3 AC kW.

Plus the charging cable ie EVSE will have a very small current drain that is 24/7.
 

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The Lear EVSE was later determined to be defective. I am not sure I would trust their data.
 
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