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You mean,even with the car turned OFF, the a/c and/or heat will still come on?
What he meant was that, the A/C-heat on/off position may internally change while the car is turned off, and hence the GOM number will shift accordingly when the car is turned on. Not that the A/C-heat will run while the car is turned off. The second paragraph is about the car turning on both the heat and the A/C in auto mode. I personally hate that myself as well, so I just use either LO or HI setting.
 

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Discussion Starter · #23 ·
Due to weather conditions, I refrained from driving since my original post on Friday.

And, when I went out this morning, the GoM was still at 202 (0 drop since 8/12.

Also, when I ran my errands, it acted like it always has.

Now, I wonder, if my original issue was actually address?
 

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Discussion Starter · #24 ·
After 2 more days (12 hours each day, same time frame a bit after 07:00 to shortly after 7:00) of back to back charging (due to low SoC, 77 miles/28%), yesterday saw 56 miles added (from 77 to 133; or 4.6666666667 miles/per hour of charging at12 Amps; Today, the same circuit added 65 miles (from 133 to 198; or 5.4166666667 miles per hour of charging at 12 Amps).

 

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After 2 more days (12 hours each day, same time frame a bit after 07:00 to shortly after 7:00) of back to back charging (due to low SoC, 77 miles/28%), yesterday saw 56 miles added (from 77 to 133; or 4.6666666667 miles/per hour of charging at12 Amps; Today, the same circuit added 65 miles (from 133 to 198; or 5.4166666667 miles per hour of charging at 12 Amps).

It’s probably less confusing just to look at the energy screen that shows how many kWh used. When you charge, the number goes down, as you drive, it goes up. Basically, it is the numeric value of the green “gas gauge” to the left of your speedometer. Miles added per hour of charging is t the best way to think about it because you haven’t driven those miles yet. You might drive faster or slower. There might be more or less traffic. It might be a different route with more or fewer hills. Maybe you’ll have more people or stuff in the car. It’s kind of like putting gasoline in your tank and saying, “I just added 372 miles to my tank.” You added a certain amount of gasoline. Just like you add a certain number of kWh to your battery.
 

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As I've said, it is a waste of time to worry about the Bolt's GOM. My reply at post 13 still stands.
 

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Tony,

You seem to be amazed that changes are happening while the car is "off". I put it in quotes because it's not actually "off". There are systems running in the background on every modern vehicle as long as 12V power is available.

All of the underlaying systems are black boxes, with unclear inputs. As stated in a previous post, just something as simple as a temperature change can modify the output of a system even though you personally haven't touched anything and the system is seemingly "off".

I know it's frustrating, but it simply isn't going to behave how you expect. The GOM has been engineered with heuristics that will change behaviors even when seeming all the inputs are static. The Bolt doesn't charge miles. It charges kilowatt hours. And the expenditure of a kWh simply doesn't guarantee a certain number of miles, no matter if the route is the same, the speed is the same, and the temperature is the same.

I know that most of us used to drive cars that simply didn't have a remaining range display. I don't remember having discussions about filling up, driving the same way every day, and having to fill up again on different days. I'm sort of curious about the obsession with the guess-o-meter and its accuracy.

As some of you may know, my daily driver is a FIAT 500e. It's GOM is much worse than the Bolts. I can start the day with the GOM on 84 miles, drive 4 miles down the road, look at the GOM and it's down to 68 miles, with a down arrow. I fear that some folks would completely flip out seeing that. But it's normal behavior as it adjusts to the current efficiency. So, I generally ignore it.

ga2500ev
 

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Ain’t it the truth. It’s a good thing that the exact quantity of electricity is easily and accurately quantified to make the GOM “fairly” accurate.

Just imagine if it was anything like the fuel level sender in an ICE gas tank. You would have a full tank for the first 80 miles for a GOM reading of 260. Then it would lose 2-3 GOM miles for every one traveled until it says you are dead on the side of the road for the last 80 miles.

Or the reverse. How soon we forget the accuracy of the typical gas fuel gauge 🙄
 

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Discussion Starter · #30 ·
As I've said, it is a waste of time to worry about the Bolt's GOM. My reply at post 13 still stands.
and
Tony,

You seem to be amazed that changes are happening while the car is "off". I put it in quotes because it's not actually "off". There are systems running in the background on every modern vehicle as long as 12V power is available.

All of the underlaying systems are black boxes, with unclear inputs. As stated in a previous post, just something as simple as a temperature change can modify the output of a system even though you personally haven't touched anything and the system is seemingly "off".

I know it's frustrating, but it simply isn't going to behave how you expect. The GOM has been engineered with heuristics that will change behaviors even when seeming all the inputs are static. The Bolt doesn't charge miles. It charges kilowatt hours. And the expenditure of a kWh simply doesn't guarantee a certain number of miles, no matter if the route is the same, the speed is the same, and the temperature is the same.

I know that most of us used to drive cars that simply didn't have a remaining range display. I don't remember having discussions about filling up, driving the same way every day, and having to fill up again on different days. I'm sort of curious about the obsession with the guess-o-meter and its accuracy.

As some of you may know, my daily driver is a FIAT 500e. It's GOM is much worse than the Bolts. I can start the day with the GOM on 84 miles, drive 4 miles down the road, look at the GOM and it's down to 68 miles, with a down arrow. I fear that some folks would completely flip out seeing that. But it's normal behavior as it adjusts to the current efficiency. So, I generally ignore it.

ga2500ev
I understand loosing some mileage when the car is off due to back ground stuff running (though, 20 to 50 miles drop seems f'n ridiculous).

But, how can a fixed rate charger charge at different rates?
 

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Try just turning the AC on/off and waiting for the GOM to change. Ditto for defog and heater.

Try not charging at all and seeing if the GOM changes from one night to the next, esp. if you power up for maybe a minute or two.

We already told you that the battery doesn't contain miles. Trying to ascertain energy based upon the GOM is pointless.

If you are charging where the battery will rise above 27 C (80.6 F, see Battery conditioning), then some of the energy coming out of the wall ends up being used to do battery thermal management.

I already pointed to difficulties in determining state of charge % and this is w/o any black box (GOM with its algorithms).

If you really care about measuring how many kWh are coming out of the wall, then add an electric meter inline or use an EVSE that will tell you (e.g. ChargePoint and Juicebox should). Don't use a Kill-A-Watt for more than intermittent measurements and certainly not for multiple hours of charging (Using my Voltec charger on a Leaf? - Page 3 - My Nissan Leaf Forum).

You will really be hating things when you start comparing these numbers to winter (esp. the coldest times of year), then to spring (esp. when temps are where you don't need to run the heater nor AC).
 

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and

I understand loosing some mileage when the car is off due to back ground stuff running (though, 20 to 50 miles drop seems f'n ridiculous).

But, how can a fixed rate charger charge at different rates?
What rate? If you are talking about miles added per hour, that is meaningless because you're basing it on the GUESS-o-meter.
 

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But, how can a fixed rate charger charge at different rates?
You've given no evidence to support this assertion. The closest data you can gather to support this assertion is either capturing the number of kWh expended to charge the battery from a specific SOC (using a device like a Kill-a-Watt that can actually support multiple hours of charging at the max EVSE rate) or by getting a precise measure of charging time again from a specific starting SOC.

Without one or the other, there's no way to assert that a fixed rate charger is charging at different rates.

ga2500ev
 

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^^^
Yep.

If one had an EVSE that logged the power levels which you could view, that'd help a LOT. Here's a graph of charging a former Leaf to 100% at work: Charging capability with 3.6 kW on-board charger - Page 2 - My Nissan Leaf Forum. 2-3 bounces at the end on '13+ Leafs is normal when charging to 100% via L2.

Curiosity Only - Near-100% Charging Behaviour - My Nissan Leaf Forum has finer resolution as ChargePoint L2 commercial EVSEs when not under Charge More EVs with Power Management | ChargePoint only show graphs with 5 minute resolution/intervals.
 

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Discussion Starter · #35 ·
You've given no evidence to support this assertion. The closest data you can gather to support this assertion is either capturing the number of kWh expended to charge the battery from a specific SOC (using a device like a Kill-a-Watt that can actually support multiple hours of charging at the max EVSE rate) or by getting a precise measure of charging time again from a specific starting SOC.

Without one or the other, there's no way to assert that a fixed rate charger is charging at different rates.

ga2500ev
I am not in the habit of falsifying information when I post something.

And, as a former Q.A. Representative for the DoD, I have an electronics background. So, I know that at a certain Amperage, the current draw will be a fixed amount.

So, if the current is a fixed amount, the numbers should remain constant. But, they aren't.

However, since all I have are numbers, it is impossible to provide any evidence at this time.

But, if you wish, the next time I charge up, I will take a before charge picture of the GoM, and a after charge picture. Would this be sufficient?
 

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If you are talking about miles added per hour, that is meaningless because you're basing it on the GUESS-o-meter.
Instead, use kWh added, based on percentage of charge from the app.
 

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I am not in the habit of falsifying information when I post something.
A request for information isn't an indictment of falsification. You simply don't have the information necessary to make the assertion that a fixed rate charger is somehow charging at variable rates.
And, as a former Q.A. Representative for the DoD, I have an electronics background. So, I know that at a certain Amperage, the current draw will be a fixed amount.
No one has disputed that assertion. We can agree that the number of kwh delivered if an EVSE is plugged into the same vehicle for a fixed amount of time under similar conditions will be approximately the same.
So, if the current is a fixed amount, the numbers should remain constant. But, they aren't.
As I keep telling you, you don't have the right numbers. If you measure the number of kWh transferred, they will likely be close to the same every time. But you keep trying to translate that to miles traveled and miles on the GOM. Neither of those values are dictated by the number of kWh transferred even if all of the the conditions are supposedly the same. There are hidden input variables, hidden heuristics, and hidden algorithms that are manipulating those values. I don't propose to tell you what those may be, as they are hidden. But because of them you won't get constant values. You'll have to ask the GM/LG engineers why they did it that way. I posit their answer will involve predictive modeling in order to offer more accurate estimate of remaining travel given the conditions.
However, since all I have are numbers, it is impossible to provide any evidence at this time.
What's needed is a separate measurement outside the current system. As both @cwerdna and I stated in previous posts either an EVSE that measures transferred current or something like a kill-a-watt that can survive a EV charging session is needed to measure the amount of input power.
But, if you wish, the next time I charge up, I will take a before charge picture of the GoM, and a after charge picture. Would this be sufficient?
No. The GOM is a unreliable narrator in this story. That's what driving you crazy. I charge my FIAT to 100% every day. And every day the GOM has a different value on it. Without the algorithm and specific inputs that it uses to generate its output, there's no actionable information from the GOM.

In the past I proposed that the Bolt should post exactly 240/259 miles on the GOM after every 100% charge. I was laughed out the forum. I now ask those who were chuckling then to take a look at this thread as my justification for the suggestion.

ga2500ev
 

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In the past I proposed that the Bolt should post exactly 240/259 miles on the GOM after every 100% charge. I was laughed out the forum. I now ask those who were chuckling then to take a look at this thread as my justification for the suggestion.
FWIW, it seems like Tesla's range meters (not really a GOM, but of a different type) AFAIK do generally charge to the same value at full charge for a given setting (e.g. ideal vs. rated range). However, even with that, just because it says some value (say 250), doesn't mean you will get 250 miles on a full charge unless you drive with efficiency at or greater than whatever the unpublished miles/kWh value was (or in Tesla's case, Wh/mile).

Perhaps the OP desires a display like the above?

But then, I believe their "full" values decline due to battery degradation, it sounds like they play with their algorithms a lot AND if How I Recovered Half of my Battery's Lost Capacity is correct/mostly correct, certain usage patterns can make that full value go lower, making it incorrectly appear as though the car has lots of degradation.
 

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Tony values consistency over accuracy. There are a group of folks that if you tell them the car gets 259 miles, they expect to both see 259 miles on the meter and to get 259 miles when they start from 100%. The second part of this of course is impossible as the actual mileage from full to empty varies greatly on a wide variety of conditions. But the consistency of the first part actually is possible to do.

But then you'll get GOM's like mine on the FIAT where after a 5 mile drive, it adjust to actual conditions possibly dropping 15 or 20 miles of projected range. Personally, I don't think it's very helpful. But maybe is offers comfort to those who need to see a consistent number based on consistent behavior.

ga2500ev
 

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Tony, you aren't adding miles. You are adding kilowatts. Check the energy screen that tells you how many kilowatts you have used. Let's say it says you've used 30 kWh. If you charge at 12a 120v (1.44kw) for 5 hours, you should be adding about 7.2 kWh. That display should now read 22.8 kWh. There are some losses in converting AC to DC in the onboard charger, and your voltage may not be exactly 120v, but you get the idea. This should be consistent.

The GOM is GUESSING (the G in GOM) what your mileage will be, based on a bunch of factors... and as far as I know, nobody here knows what all the factors are and how far back they are looking. We do know that some amount of your previous driving has a huge effect it. So does temperature and climate control setting. The GOM doesn't know how you are planning to drive or when. It doesn't know what the weather is going to be. It doesn't know how much regeneration you are going to use. It is a guess.

If you like facts and numbers, use kilowatts. If you like approximation and guessing, use the GOM.
 
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