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Discussion Starter · #41 ·
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
You don't know me. So, please do not make assumptions. Because, when you assume, you make an ASS out of U and ME.

Perhaps, we are not understanding each other.

But, I did have a first this morning, see Massive drop on the range display (GOM/Guess-O-Meter)
 

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Discussion Starter · #42 ·
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.
Still, shouldn't the GoM be pretty close to accurate?

I know when I first got the car, there weren't any of these dropped/increased miles (see link, and my comment in above post).

But, isn't that since the last full charge (which I only did once, and the meter didn't reset)?

So far, the outside temp shouldn't have a much of an impact. And, for my climate settings, it has only been changed once, then back to the original.

Just seems weird that these variations are happening. Especially as mentioned in my other post.

So, maybe something screwy in the software?
 

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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?
Even with a fixed rate charger, the vehicle will adjust the amount of actual current flow to accommodate the charging conditions. Unless you continuously monitor or log the charging status, you cannot be certain if the rate changed or not mid-way. If this sort of flexibility was not programmed into the charging software, the battery's lifespan would be cut short.

Anyways, this is the reason why you can't determine how much energy was transferred to the vehicle by simply multiplying the time and the "nominal" rate. You must look at a log or metering equipment to determine this. Since you have electronics background, I think you know this, but I'm just covering my bases here. Apologies in advance.
 

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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.
I know this is a job for someone else in the forum (wink wink), but it's, uh... kilowatt-hours.
 

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This is again why my reply in post 13 still stands. It is not worth wasting any more time on the GOM.

I've seen plenty of Bolt GOM wonkiness and sudden drops besides having had experience w/the Leaf GOM for almost 8 years (e.g. starts at 80 miles, drive 8 miles and it's gone up to 88. Go up the steep hill that is highway 17 and the GOM drops by 40 miles after driving 10 miles.)

Your usage of auto on the HVAC (I don't use that) only adds to the confusion and stuff going on behind your back.
 

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Still, shouldn't the GoM be pretty close to accurate?

I know when I first got the car, there weren't any of these dropped/increased miles (see link, and my comment in above post).

But, isn't that since the last full charge (which I only did once, and the meter didn't reset)?

So far, the outside temp shouldn't have a much of an impact. And, for my climate settings, it has only been changed once, then back to the original.

Just seems weird that these variations are happening. Especially as mentioned in my other post.

So, maybe something screwy in the software?
If 3+ years of driving my Bolt has taught me anything, the GOM is what the vehicle thinks is pretty close to accurate as far as drivable range is concerned. And this is based on a myriad of factors that is not completely transparent to the driver. Even if no settings were touched or internally changed, the number will change as the car sees fit. As an example, just a slight shift in the battery voltage while being parked for an hour can move the GOM number by several kilometres. I do agree that it could look screwy in some situations.
 

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It's like imagining that your breakfast contains staircases climbed.
I actually think this is a really cool way to think about what I eat. You're right about the mile thing but I'm going to go grab me a marathon right now in the form of a Snickers. Fun!
 

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You don't know me. So, please do not make assumptions. Because, when you assume, you make an ASS out of U and ME.

Perhaps, we are not understanding each other.

But, I did have a first this morning, see Massive drop on the range display (GOM/Guess-O-Meter)
I'm not making assumptions. You have 6 posts in this thread where you've stated that if you have a consistent behavior then you should consistent result. That is stating that you value consistency.

A 10 mile drop on the range display isn't massive. It'll occur if the HVAC comes on. Or if the temperature changes. Or if you drive too fast.

I understand perfectly. You want the car to operate the same way every time you use it. It's not going to do that. But instead of simply accepting how it operates, you seem determined to suss out the thing that is wrong that's causing it to behave inconsistently.

I'm going to assume that you will not listen to the explanations we have offered to you. So, in this case, I'm out.

ga2500ev
 

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I'm not making assumptions. You have 6 posts in this thread where you've stated that if you have a consistent behavior then you should consistent result. That is stating that you value consistency.

A 10 mile drop on the range display isn't massive. It'll occur if the HVAC comes on. Or if the temperature changes. Or if you drive too fast.
To make this more concrete, the heater on full can pull up to 7.5kW. The AC on full has done up to ~5kW (not clear if it was just for AC or also doing battery conditioning at the same time). Meanwhile, on a flat road, going 40mph, I'm typically using less than 7kW. Even at 60mph, usage is usually only ~15kW.

The good part is that the HVAC seldom is running full tilt for more than a brief period, but it's not hard to see why it could have a huge impact on estimated range.

Main issue for me is that the auto-defog setting likes to reset itself every so often. And believe me, I notice when the GoM jumps/drops. But then again, I keep the HVAC off or on fan-only 95% of the time.
 

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Main issue for me is that the auto-defog setting likes to reset itself every so often.
Exactly. I've gone in and turned it off, multiple times. I've sometimes seen it mysteriously back on.

I live alone. Nobody else drives my car. Nobody else has my car keys.
 

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Exactly. I've gone in and turned it off, multiple times. I've sometimes seen is mysteriously back on.

I live alone. Nobody else drives my car. Nobody else has my car keys.
Do you have a cat? They can be quite clever and mischievous... ;)
 
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