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This may be an 'old' topic, but I wasn't sure what search terms to use to find out if related postings exist.

While cruising on a relatively level stretch of interstate (at least as 'level' as you can get in San Diego), traffic was light enough for me to try keeping my speed at the most optimum for the best MPG. For well over 10 miles I maintained 80-90 MPG :D

Curiously, at the start of this run, my battery gauge was roughly at 50%.
Keeping a constant eye on the gauges, I saw NO assist or regen activity throughout the entire 10+ miles - yet, at the end of the run my battery registered nearly full :!: :?:

Is this a normal 'feature' of the Insight. I would have thought regen of nearly 50% battery capacity would result in at least some green bar activity on the gauge!

Everytime I think I got this car figured out, I come across a new behaviour :shock:
 

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charge

That is the classic "hidden charge". It is a normal operation. After the hidden charge, your mileage will be better.

Many posts on ICN about the subject.

Willie
 

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Yep. Almost all my charging comes from that trickle charging (since I rarely stop). While cruising down the interstate, I can watch my gauge climb from 3/4 full to just 1 bar shy of full.
 

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Hello HB,

After several "recalibrations" from more knowledgeable forum members, and subsequently after about 8 months of observing actual assist and regen current (with some special modifications and related instrumentation) in relation to the indicated orange and green bars, I can offer the following facts:

1) The assist indicator (orange bars) are proportional to the actual assist current in all of the cases you are likely to encounter. (We've found exceptions, but they're only related to malfunctioning modifications that have since been fixed.)

2) The "hidden" charge is usually just enough to maintain your 12V battery charge, which powers the Insight's utilities. This is not necessarily enough to increase your indicated battery pack state of charge.

3) There is a forced charge that occurs when the Insight's battery controller decides it is needed. This is not random, but the algorithms remain a partial mystery to me. This forced charge occurs most of the time when the headlights are on, unless the indicated state of charge is over 90%. You won't necessarily see any green bars while this is happening. This is what I believe you are identifying in your initial message on this thread.

4) The regen indicator (green bars) is displaying "fiction". While there may be some partial correlation to the the actual charge current, this can't be trusted. (I'll forego the extensive data and details for now.)
 

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I had some warranty work done today. The charge indicator showed dead afterwards and climbed slowly until "bam" it jumped to nearly full. (This is another example of non linear activity.)
 

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nemystic said:
1) The assist indicator (orange bars) are proportional to the actual assist current in all of the cases you are likely to encounter. (We've found exceptions, but they're only related to malfunctioning modifications that have since been fixed.)
Not to seem too argumentative Brian but IIRC there's only been one ooold post that provided any data, Armin's:

IMA Charge/Assist gauge
http://www.insightcentral.net/forum/viewtopic.php?t=582

From his data the only _accurate_ conclusion that could be drawn is that if the gauge is showing assist that current is flowing out of the IMA pack. Conversely for charge.

IIRC the MCM / BCM control logic is now in its 3rd revision so details will have to be qualified as to the controller that is installed.

There are qualifications that also contradict your other points too. e.g. hidden charging can "replenish" a relatively low SoC. But you'll be hard pressed to experience the effect in your terrain. ;) And during WOT acceleration the corresponding near "full" assist initially starts with a relatively high current flow but rapidly ramps down after a few seconds without a corresponding proportional reduction in displayed assist.

The control logic by necessity is quite complex and I sincerely applaud you effort to condense it so briefly.

HTH! :)
 

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nemystic said:
2) The "hidden" charge is usually just enough to maintain your 12V battery charge, which powers the Insight's utilities. This is not necessarily enough to increase your indicated battery pack state of charge.
Then how come my battery gauge slowly climbs from 3/4 to near-full just by driving down the interstate?

Answer: Cause the hidden trickle charge IS enough to increase the high-voltage battery's SOC.

:)
 

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To the best of my knowledge, my battery control module in my vehicle is the original 2001. I don't claim to know the differences between the various revisions of BCM's. Consequently, the information I am offering is applicable to this particular BCM revision.

There is a hall effect sensor that outputs a voltage in direct proportion to the assist/regen current. For 8 months, I monitored that voltage with a DVM on the dashboard.
The hidden charge is not indicated in that signal.

The regen indicator (green bars) does not indicate accurately what is going on. This is fact, not opinion.

With the MIMA modification, it is possible for green bars to show when there is no regen at all (other than perhaps the hidden charge).

It is also possible for there to be a low level forced charge (not to be confused with the "hidden charge") without any green bars showing. This condition occurs when the BCM algorithms determine it is needed, but most often when the headlights are on, or after a significant discharge period.

I believe this low level forced regen is what you are referring to, as with no green bars displayed, it is in effect, "hidden".
 

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I just read Armin's observations from 2003.

"When green bars are lit, you know there is some charge current flowing. Again, more bars more current. However, no bars doesn't necessarily mean no current! Many times (especially with the lights or AC an), the car decides to charge during cruising. In this case, the green bars will only light if the SOC gauge is less than about 2/3. "

My observations are consistent with his.
There is only one observation that I would disagree with.

"When green bars are lit, you know there is some charge current flowing."

With the MIMA modification active, this is not necessarily true (again, with the exception of the "hidden charge"). Since Armin is now a MIMA user, I expect he would have the same observation at this time.
 

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nemystic said:
"When green bars are lit, you know there is some charge current flowing."

With the MIMA modification active, this is not necessarily true (again, with the exception of the "hidden charge"). Since Armin is now a MIMA user, I expect he would have the same observation at this time.
With the needed caution that MIMA discussions are off topic and will be removed, see:

http://www.insightcentral.net/forum/vie ... php?t=5237

and follow-up as the links direct you should you desire further MIMA discussion.

I do understand how MIMA couldn't be left out of this topic. But further MIMA "discussions" of this type need to be taken to the approprate forum (off IC).

IIRC Armin's measurements were done witn an inductive amp clamp on the main IMA feed to and from the motor :arrow: IMA battery pack. What all the differences are remain to be seen and are only a "technical" debate. I don't see how it can be helpful to "know" or of any real value except to again bring the MIMA topic to this forum :|

Sincerely,
 

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Mike, If I recall correctly you used a large scale linear voltmeter to measure current initially. Certainly a good digital voltmeter would be the preferred method to get an accurate reading at low levels of charge, which is what we are debating here.

As I have experienced and mentioned above the SOC meter can suddenly increase without an equivalent increase in charge taking place. This, as experienced Insighters know, is due to drift in the calculated state of charge being corrected when the computer sees a higher voltage than anticipated. (positive recal) Since the Insight will slowly recharge the IMA pack while cruising, this could explain a seemingly large jump in SOC without indicated charging. Since this self adjusting mechanism creates no discernable decrease in performance or mileage, it likely happens more often than we notice. The fact that Henry was maintaining lean burn and had this occur over just 10 miles, suggests that significant charging was not in fact occurring.
 

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Hi Kip,

The positive recal phenomenon you describe is something I've seen several times, and I would consider it separate and distinct from anything else I've tried to describe in this particular thread.
It seems as though they most often occur after either an IMA reset, or a "negative" recal. Sometimes, it's just a pleasant surprise.

I always enjoy reading your signature: :)
"If having fun in an Insight was illegal I'd be in big trouble!"

[mod edit, see rule #18, 19 and the General rule at the end]
 

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Good point Kip
With the boost charger, I have to watch that transition, so I have quite a bit of experience . The M meter that some of us have in our car reads amps quite nicely. Each led of regen represents 12.5A of current into the battery. The latest M meter software has a PWM control of the led brightness so even one amp shows up clearly.
Over 3/4 SOC, the green leds go out, but the current stays the same, there is about 8-10 A. this current drops in several steps before turning off at the 1-2 bars point in the SOC.
20 A of regen is going to slow down the car unless you are going down hill. the 8-10A of hidden charging as Willie said, will drop your MPG for the same reason, unless you can only regen when needing to drop speed anyways.
Thats been my experience, some of the other guys with an M meter, may have different experience.
 
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