S-Prihadi

Charge as needed when voltage hits 12.4V. This is a sign that it is low enough to benefit a charge but not low enough to hurt hard your battery discharge/charge life cycle.
But do make sure to wait for all computers in the car is sleeping, otherwise your door opening triggers electrical load and computers waking up, and it will show battery voltage a bit lower than
if compared to a pure low drain stand by mode with all computers sleeping.
For my model, after a day of parking : I wait usually 10-30 minutes , after I opened the door and then opened up the hood , to read the battery voltage. There is a open-hood sensor too on mine.
You can profile this within the next 2 weeks to see how many days parked will get you to 12.4V volts.

BTW, I managed to track a bit of parasitic load in my E400. It is the memory stick USB which has my songs. I keep it hooked at the USB connector ( at glove compartment ) all this time.
I think it is making my sound system not sleep 100% and snoring ..LOL. Now I am draining only 65-100 milliamps. Thanks again to Sunnyslope48 for "waking me" up.
I will do more test sometime soon, to re-verify this, to be sure of the actual milliamps the USB memory stick is eating up over a few documented hours.

Easy to test if your sound system is behaving like mine. Without car key or ignition OFF totally ( I do not use push button start, I don't like it ) and key fob as far away as possible out of radio range,
plug in a memory stick which has a LED to show its handshake to the host system.
If those LED lights on the memory stick lights up, you know that its host (the car sound system) is not totally sleeping. I do not know if this is a default to all W212.
My audio system is the lousy one with no navigation/GPS or rear view camera, el-cheapo 2014 version I guess for 3rd world countries. But I do have twin small LCD monitors for rear passengers and
a DVD/CD player at the rear seat.

.

kajtek1

Batteries are chemical unit, where mechanical principals don't apply and that is why it is so hard to measure their condition.
They don't like charging & discharging cycles, but do like to be maintained.
So the HF maintainer is the best thing you can do when you have car sitting for weeks.
Than the battery who lasted 13 years in our ML has never seen a charger. For years it was our Sunday car and then it would sit for up to 5 weeks with alarm on and still start on its own power.
New cars should have more efficient electronics, so draw less current while at sleep.
I always had lot of batteries RV, boat, equipment and when I had them sitting for 6 months with maintainers on, over the years couple of times I had maintainer failure who killed the battery, so this still require occasional monitoring.
I'll be leaving my cars for 3 months this summer and I think just pulling the clamp off is the best way to do it for that period.
Would that be 6 months, I'd hook up maintainer.
I have several chargers who do equalizing and even some RV owners with big battery banks prize them, I had 4 of golf cart batteries in my previous RV and did it once or twice. The cheap batteries were sitting 6-8 months every winter in dry storage and lasted 10 years.
So once again, from sketchy technical data the Stanley is no maintainer and hooking it up to car sitting just for days can do more harm than good.

LALALAND

I just charge up my main battery yesterday for 4 hours after it went to stage 7 floating. Last time I hook it up was in October and around 4-5 hours too. The first time I hook it up it take 6 hours for it to change to float stage 7. Charging the battery 2-4 times a year shouldn't hurt that much if it does damages then will be minimal. Currently charging my other car that I drive on weekend only.

As for Eco stop/go, I kind of want it and kind of hate it. My weekday driving require 11 stops signs and about 2 dozen traffic lights. When it activated (a year ago), I was inching along toward stop sign or traffic lights, which is pointless. Once I was stop in the middle of a intersection for a left turn, the engine stop. It's kind of dangerous as I was trying to cut in between traffic flow gap, and had to gun it once the engine start (there is a delay when engine start and enough power to move fast out of the on coming cars). Kind of want eco stop/go it cause I'm getting 17 mpg (actually around 16 at pump) with my average speed of 14 mph from trip computer with past 16 month data. The freeway mpg are over 27 around 75+ mph

Wish it activate on demand with brake HOLD when I'm waiting for 2 minute traffic lights, not random stop while inching forward toward stop sign or traffic lights.

Mr.Fly

Wow! Thanks for the detailed explanation of the inner-workings of the ECO start-stop system. I'm so glad my car doesn't have it, but it's enlightening to see how much (sometimes misguided) effort went into saving a tiny bit of gasoline during stops.

Mr.Fly

Discounting the description of how the new ECO cars don't like a highly charged battery, I would recommend keeping the batteries on a good tender, such as a CTEK. I know quite a few exotic car manufacturers provide a basic CTEK with a new car purchase, because they know the cars won't be driven much. These tenders come with pigtails that you can splice onto the battery, thus making plugging them in easy. You can also get a plug that fits into your cigarette lighter or accessory socket (if that is "Live" when the car is off), and maintain the battery through that. FWIW, I keep my sporadically-driven car plugged in anytime it's in the garage, but my car isn't ECO Start/Stop-equipped.

Actually, CTEK even offers a charger specifically to address the needs of cars with ECO Start/Stop. It's obviously a marketing-driven basic model, but it's worth a look if your needs are specific.

CaliBenzDriver

hwy speed with AC_ON: 12.0V discharge under load

Discharging at running idle: -68Amps (I've seen it -100A \"charge")

Hwy speed @11.9v ... fasten your seatbelts !!!

charge abuse @62A under 14.7V (900W) idle
German cars and many other Japanese and US are built based on BOSCH state of the art CAN-Bus controllers and software technologies.
Designs keep evolving non-stop. So every MY feature is similar but at the same time quite different when you look closely to version level. Some cars have regenerative undercharge, some ECO/STOP, etc... As time goes by designs get refined and some existing issues get fixed.

We have to be careful not to generalize issues across all W212 years, these machines have the same bones but are different.

Unless there is a TSB repair published, nothing is official! The countless problems on my MY14 M276 may not be found in previous or later models. I can say that getting the charging module updated (more stable charge voltage) helped a lot with aggravating CanBus errors: Distronics, Steering, Keyless, Blind Spot, Active Collision Beep-Beeps. etc. Thank God I dont have Parktronic to get milked with!

In a nutshell, best thing to do is use the "Secret Menu" to look and understand what your battery charge is up to (Volts & Amps). I started doing that because my ECO was crazy unlike other models where ECO works very consistently. I got to study the ECO design for its countless conditions. Charge rate is dynamic on my MY14. Charge is done mostly while *decelerating* but can occur during acceleration too after a long ECO Stop with AC (I get ENG restart below 11.7V). Headlights_ON peg voltage to 13.4V minimum or above otherwise it can go down to 11.9V if cruising over 1Hr on HWY without headlights. Plenty of room for PITA (limp mode) and battery abuse.

Long story short when you can point out a clear problem, a known solution may be found in the hundreds of applicable TSBs. All great learning

S-Prihadi

Any Ctek charger of 5 amps (mine ) is so low power for a 80 - 90 Ah battery, and it is smart enough too float or trickle/float charge when battery is full.
You can use it every other day, just don't permanently hook it up to your battery for days and days. Its heat dissipation is bad, all plastic. I have the 5 amps one.

Our W212 alternator is more brutal amps hour wise than any Ctek of 5 amps and it is charging our battery all the time when engine is running.
I am not being rude, but Kajtek1 experience with Spanish made Varta ( assuming it is a starting battery ) lasting 13 years is like hitting a lottery.
I or my friends or mechanics , for cars starting batteries do not get this kind of lottery, not in our climate. 7 years is the best MB/BMW battery life, trunk located ones according to them on original OEM batteries. No charger assist.

Electric Golf carts usually use deep cycle battery. Deep cycle battery when being used cautiously will last longer than a traditional starting battery.

There are some rather expensive 12V marine deep cycle which I seen lasting 10+ years, but they are not good for starting battery for their CCA value vs Ah rating and size/weight.
This is the brand http://www.rollsbattery.com/ . Hatteras Yachts usually use this one, at least in the old 65 footer 1985 - 1995 models which I seen. I don't know how good Rolls batteries are today.

Ctek is basically a battery maintainer once the voltage level of the battery has reached the float charge level.
There are some very low amps battery maintainer at only 1.25Amps, Ctek has a 0.8 amp unit too.
I can't say how good is Ctek longevity , my barometer is a 365 days a year 24/7 charger work profile on my boat and friend's boat and it it can last 7-10 years, it is then a decently good one.
When I use my Ctek, I use a fan to blow it cooler and place it on its side. Its hottest part is the top and bottom, hence I placed it on its side for maximum cooling.
If without a fan, my Ctek5 amps goes to 50+ Celcius ( 122F ) and I don't like any electronics to be that hot. Heat kill them fast.


I am keen to verify CaliBenzDriver information on the possible "undercharged profile" on my year 2014 M276 3 liter W212 with ECO start/stop , does it actually exist ?
I do like all these new DC electrical stuff 101 on a car using modern CAN/SAM.


When I replaced a new battery, I do not wait till it fail to start my engine.
I use my ears to verify slight lag in the starting of the engine and the sound of the starter. It has worked well for me since 1983. I don't need to measure its voltage during crank.
Only on my E400, its new Varta AGM of July 2018 change is a voltage measured after 2 days standing by, not by ear, since this is a used car, I want to "reset" all maintenance items.

.

CaliBenzDriver

CTEK chargers are European top of the line smart chargers. It's nice how they are multistage and go automatically into float cycle for long term maintenance.
My unit is a MUS4.3 that gets up in temperature (cooks internal caps!) like S-Prihadi points out.

I believe it is good to charge any lead-acid/AGM battery with CTEK once every month or two in order to balance the cells and hopefully remove a little sulfation or prevent extra (yeah right, good luck removing lead sulfate)
BUT if your W212 has the "regenerative" feature, beware of the abuse the car charging algorithm is going to use to re-DISCHARGE a fully charged battery.

Regenerative smart charge feature requires to keep the battery at low state of charge to accept charge during coasting cycles. As soon as the battery Mgt computer realize you charged your battery...it will discharge it. (FYI: MB dealers use BATTERY MAINTAINERS to provide HIGH float current @12.7V when working on cars... but NOT "chargers" that would charge the battery under higher voltage 14.4V).

Nugget: more POWER ... direct injectors sound:
Pay attention to the ticking sound of the ultra-high pressure direct injectors with a fully charged battery: sounds like crickets unlike when the battery is back to its usual working undercharge level... injectors are way more quiet.
Injectors being very voltage sensitive, a higher voltage means kick-*** power... until the wide-band O2 sensors re-adapt fuel trim to the richer mixture, then slow-poke is back ! (Car voltage scales from 11.9 to 14.9V so ENG "mood" depends on Battery charge!)

Enjoy... love thy Benz !

kajtek1

I have 2 of suppose the same 2014 E250 BT and driving with ScanGauge noticed that they recharge quite differently.
First I never see below 12V, what might be that dashboard shows ECU voltage, what usually is 0.5V lower that the supply and my ScanGauge seems to monitor the 2nd.
One of my cars was making perfect regenerative charging when I was coasting and then it would peak when I hold foot on the brake.
The other car has charging making completely no sense as it would charge high on acceleration and drop the charging on braking.
The only difference I can think about is the older battery on 2nd car, but the battery works just fine and this is happening for a year.
For short time I had Autotell scanner who had program for ECO showing 12 parameters who can affect the performance.
I refunded the scanner as iCarsoft has better value, but wonder if such data could be used in live traffic.

ygmn

Yall saying the car uses the alternator for regen braking?
does sound strange as it is not rated very high to really have much braking forces thru engine back thru tranny to wheels....
IF altrnator was putting out 100Amp @ say 14.2VDC = 1420 watts = 1.9hp which heck is less then the friction in all the drivetrain....from wheels to engine front crank pulley.

Not like these cars (EXCEPT HYBRID) have electric motor in drivetrain between engine and wheels.....

kajtek1

It is not just fuel saving, but emission savings.
When you are talking 60 mpg and want to get 62 mpg, each kilowatt counts.
It is like older fuel injectors would still drip fuel (gas or diesel) when braking, when digitized cars shuts the fuel to 0
Than again, the publications say over 5% fuel saving. That saves you for nice dinner every year

ygmn

SO how does it REGEN brake?

kajtek1

https://auto.howstuffworks.com/auto-...ve-braking.htm

CaliBenzDriver

YES it is "REGEN" but poor man version: "regenerative charging", not "regenerative braking" because there is not enough coupling through a serpentine belt.
It slows down the engine, not the wheels.

This BOSCH design commands the alternator to charge the battery mostly when coasting instead of during accelerations.
Bosch sold that design all around including to FORD who has it as "smart alternator".

"ECO S/S" is distinct: is the real battery abuser (frequent cycles, high currents and AGM heat).
The charge controller measures actual battery health and its charge level under load with ECO cycles

I used to ALWAYS turn off ECO to prevent useless Starter/Batt wear (restart too many times during traffic crawl ).
Now I let ECO stop at least ONCE per driving cycle or at long traffic lights

CaliBenzDriver

KajTek: I totally relate to your experience with your twin E250 MY14 sisters: unpredictable moody cars.

Ridiculous charge behaviors like you witnessed "would charge high on acceleration and drop the charging on braking."
or simply quit charging: voltage below 11.x V
or discharge with -70A out of the battery then the next minute charge with 14.9V under super high Amps

I believe MY:.../14/... PCM really struggles to calculate the battery "State Of Charge" and safely quits charging instead of exploding the main AGM.

BEWARE:
Take a mn to query official safety reports at "NHTSA dot gov":
many E-class drivers reported the car electricals going dead while at freeway speed (alternator discharging an exhausted AGM.. crash main PCM?)

Benz software is sub-standard chaos (Crap ). These basic issues should be fixed automatically during the annual $300 oil change. Dealers are between a rock (OEM) and a hard place (furiously displeased customers )

Peace of mind:
pop the "SecretMenu" battery display to keep an eye on charge, especially at freeway speeds!

DFWdude

OK, how do I access the Secret Menu?

CaliBenzDriver

Go to YT: scroll to 5:40 for quick instruction

Or basically this:
Door closed
Display showing mileage
Engine still stopped
Ignition: 1 push (or 1st key position)
Steering buttons: call answer + OK
Then you can start ENG normally once BATT display is activated
Drive carefully.

After couple days/weeks, you should be able to tell if your battery charging is acting crazy or mostly working as intended.

In any case it will enlighten you to know exactly what is happening.

Hopefully this will help you gather why your car kills more AGM than tires or brakes...

[ FYI ballpark data:
my E350 M276 MY14 shows Batt: 12.0V -10A (overnight cold, ignition On, ENG Off) else around 12.2V if driven that day. ]

ygmn

SO you are saying the alternator acts as regen braking....

I kinda find that hard to beleive as it cannot draw enough power to actually develop any braking forces.

the engine by itself with throttle off will cause more braking force at wheels

CaliBenzDriver

As far as charging AGM lead/acid gel glass mat battery used on NON-electric engines:
Opportunistic charging ie. smart charging has NOTHING TO DO WITH BRAKING! Hybrid electrics out of scope here.

It's a tiny bit confusing ...
The alternator controller monitors the throttle for COASTING condition so it can trigger higher alternator load to recharge the main AGM to between 60 and 80% target charge level. This plays almost no role in slowing down the car.

S-Prihadi

Regen charging, not braking.
When alternator say for simplicity sake generate 100 amps during braking, at say 14.7 volts, that is 1,470 watts electrical and add 30% mechanical loss , say 1,900 watts.
So what happen is, the car get free battery charging power of 1,900 watts for "X" seconds, at the same time its engine needs to output 1,900 watts LESS
or approx 2.5HP LESS during de-acceleration because the power producer is the car momentum. Anytime the accelerator pedal is released, car momentum via the wheel and transmission
actually "spin" the engine...let's imagine this is a manual transmission car.

So an engine saves fuel for those seconds, engine also gets parasitic load of 2.5HP which is the same as bogging down the engine by 2.5HP equivalent. The engine does get slowed down....the engine.
As CaliBenzDriver pointed out, this is a poor man regen.


Charging Topic I am still keen to learn :

01. I am curious to learn, what if someone when charging his battery in the car, does not use the provided brass negative post at suspension well ( for mine ), but instead clip directly to the negative terminal of the battery,
therefore by-passing that Hyundai Mobis Charging chip at the negative battery terminal. Will this fool the charging chip even more ?

Now, BMW goes 1 step further. It will register a new battery to its computers/ECM , because BMW claimed that as battery aged, it need a bit different charging profile.
This actually does make sense as it is true that battery as it grows older, may behave differently as the battery plate sulfation increased.
Battery capacity is related to how much clean plates it has to allow chemical reaction from the battery acid.
Perhaps as pointed out by Kajtek1, his two of year 2014 E250BT alternator charging profile behave different and 1 car has older battery.

Mercedes does not need a new battery to be coded to the computers. Maybe MB has faith in Hyundai Mobis charging chip algorithm.


02. I been hunting around to learn of how Hyundai Mobis Charging chip works, but I never could get its real 101 on the net.
I want something as informative as the ECO Start Stop info I found ( attached ).


03. Adding more mystery, perhaps all of our cars may have country specific software/firmware and not only different versions of same country firmware based on dates of update,
which may produce different charging behavior.

This link is about Hella Intelligent Battery Sensor + Bosch smart alternator study, maybe Hyundai Mobis is similar to this ?
https://www.mdpi.com/2076-3417/6/10/285/pdf
If you spend time reading above paper, you will discover many 1st world country has DRIVING CYCLE. Maybe charging profile is linked to this.
USA driving cycle https://en.wikipedia.org/wiki/FTP-75
European : https://en.wikipedia.org/wiki/New_Eu..._Driving_Cycle
Japan : Has JC08 (2008) but I cant find its Wiki
Global, harmonized : https://en.wikipedia.org/wiki/Worldw...test_procedure

I like to emphasize "1st world countries", this is because I am from a developing country and my car may have unique charging profile based on emission reduction or energy savings being NOT a top priority.



Can Kajtek1 confirm :
CAR A -- One of my cars was making perfect regenerative charging when I was coasting and then it would peak when I hold foot on the brake.
CAR B -- The other car has charging making completely no sense as it would charge high on acceleration and drop the charging on braking.
The only difference I can think about is the older battery on 2nd car, but the battery works just fine and this is happening for a year.

Which car has older battery ?


This thread is fun....

kajtek1

The one where charging makes no sense.
I see several benefits of this system (when it works as it should) and again- cost of more frequent battery replacement is marginal
- when engine during braking has fuel cut off, alternator at high charge gives you +- 2 hp of braking power, so it is saving brake pads wear while charging the battery using "free" energy.
- than during acceleration alternator is turned off, what not only give you additional horse, or 2 so you gain better performance
-fuel and environment saving is just icing on the cake.
Getting used to ECO stops is another story. My home route is coming from freeway and 5 miles street driving with long time at red lights.
Very often ECO stop will not work coming straight from freeway, what I think is due too hot exhaust, but I learned that waiting 15 seconds and moving only 2" will kick the ECO stop.
Then when in rolling traffic, you don't want the ECO to stopping every few seconds, so I practice brake pedal modulation, when barely visible movement will prevent ECO stops.
Each feature takes different technique. When I had SBC brakes, I did practice that coming down curved freeway ramp I avoided 5 brake pumps and just hold modulated pressure on the pedal, so it was counted as single brake activation.

S-Prihadi

Okey, got some video on the alternator charging profile of my car. Too bad only 42 minutes 50 seconds video, non stop.

Parameters :
AA. Car battery been charged with Ctek to full capacity, prior to this use/test, 24 hours ago . 23rd April 2019.
BB. In the morning of 24th, I was doing 5 minutes idling test and alternator was charging well.
CC. Test done on 24th April 2019, 5PM up. I am at GMT +7


This is my semi-concrete conclusion based on what the video showed me, but I think it won't drift far from its original algorithm because 42 minutes drive is not that short.
My car, I strongly believed, does not have "undercharged profile". The followings are the notable discharge counts and duration I noted down :


01. I think, the Alternator and charging chip algorithm trying to investigate battery condition the first 3 minutes after engine start, case to note :
DISCHARGE - 2nd gear, 10KM/H and accelerating slowly to 15 KM/H
13.2 volts, -3.1 to -12.4 amps
Start 2min 26.360sec
End 2min 29.800sec Duration approx 4.5 seconds

ZERO AMPS - 2nd gear, 15KM/H and accelerating slowly to 25 KM/H
13 volts 0 amp
Start 2min 29.800sec
End 2min 37.020sec Duration approx 6.5 seconds
The duration of 6.5 seconds of non dynamic charging is what matters to me, not the Zero amps.


02. I am kind of happy to see the charging voltage and amps is so dynamic at minute 3 to minute 24th, and without any mini 1 second discharge.
I think this is the period where most electric needs/demand are already active hence no short discharge and computers chosen to fully charge my
battery after its calculation at the first engine start to minute 3.
The way the voltage are being set from 13.3 volts to 14.7 volts dynamically, and the amps from small 2 amps to higher amps.
Seems like the system is trying to optimally charged the battery by bulk and acceptance method.


03. The short 3/4 to 1 second discharges after engine start to 3rd minutes and after 24th minutes of engine running, I think it is not the system intention for discharge,
it is probably a charging current control respond which lag speed and looks like short discharge sessions.
Our W212 is heavy on electric use, my car was traveling very slow and ambient temperature 90F easy. Electric fans on some W212 models get 800 watts unit, that is a 57 amps at 14 volts.
Electric steering + other engine electrical needs and yada yada. If any of them power suckers switches ON suddenly or better to call it dynamically as needed, for an alternator to respond to
such a demand ....it takes perhaps 0.5 to 1 second and stabilized by 2nd second.
Imagine this : Alternator charging to battery at 10 amps, suddenly a device which needs 20 amps is activated, the alternator need to increase its output by another 20 amps and the
short 3/4 to 1 second discharge or amperage dip/deficit is the result.

One can confirm above if we have additional data logging current meter at the alternator positive cable output to measure its GROSS output. Sensing location is before alternator cable joins
the pre-fuse box #32* (*where we clip our positive charger clip).
Do remember , the amperage gauge we can see on the speedometer is a NET charge/discharge value to the battery ONLY.
It is not the TOTAL output of the alternator.


04. I believe that : After 30 minutes engine run, alternator and charging chip is trying to investigate battery condition further, after battery deemed fully charged.
This is when they made longer discharges of 3, 3.5 , 4, and 9.5 and 12.5 seconds duration. All long discharge duration :

NOTABLE LONGER DISCHARGE - speed 15KM/H
13.2V , low -2 amps average discharge
Start 30min 37.200sec
End 30min 40.160sec Duration 3 seconds


NOTABLE LONGER AND MORE POWERFUL DISCHARGE - speed 8KM/H
13.2 volts down to 12.8 volts and amperage was average -30 amps
Start 30min 43.940sec
End 30min 47.940sec Duration 4 seconds


NOTABLE LONGER AND MORE POWERFUL DISCHARGE - Accelerating, speed 15-30 KM/H
Down up to 12.7 volts, amperage up to -35 amps.
Start 31min 18.380sec
End 31min 30.880sec Duration 12.5 seconds


From 31min 31sec alternator was charging. Mostly under 7 amps on average.
Voltage frequently at 13.5 volts, and little time above 14+ volts
Now and then it does that short 3/4 to 1 second discharges up to minute 41.

And then at 41min 47.540sec it does bigger discharge and up to 35 amps
ending at 41min 51.060sec, so only for 3.5 seconds and lowest voltage 12.7volts

And again 1 minute later at 42min 21.180sec to 31.120sec or duration of 9.5 seconds,
it discharged at up to 35 amps and voltage down to 12.8volts.

My video stop at 42minutes 50seconds, memory card full because I have other test but at engine idle only.



05. Why I strongly believed that my car does not have "undercharged profile" is because :
When the 3 - 12.5 seconds discharges occurred, never the battery voltage get lower than 12.7 volts when discharge finally stop.
In theory I am still at 100% state-of-charge if at 12.7 volt ,more so while being loaded, albeit at the ending seconds the load is under 10 amps.
Now, becareful when looking at battery voltage under a loaded condition.
Open circuit voltage of our battery with zero load is supposedly 12.7 to 12.8 volts with no ghost/surface voltage.
If the same battery is loaded at 50 amps for say 3 seconds it may read as low as 12.4 or less due to load, not due to state of charge.
When a battery crank an engine, its voltage can drop to like 9 ish to 10 volts. I think our V6 engine starter is a 2.2kw or 183 amps at 12 volt.
What I am trying to say is, if you guys see discharge occurring while engine is running, and in anticipation of the possible "undercharged profile", do measure how many seconds the duration was,
aside from noting down the amps discharge and voltage drop. The weaker the battery , as in no more 100% healthy, the higher the voltage drop will occur if say 50 amps load applied for a mere 3 seconds.


06. If I calculate all discharges count and duration :
All combined is less than 2 minutes. Engine run is +-43 minutes, yes video limited.
Surely I am getting proper charging surplus and no deficit.
If my car charging profile is not the same as those in USA, I think I like my current charging profile
I can also confirm that my charging regime during car stand-by using Ctek charger, is not effecting the car alternator charging algorithm.

================================================== =====================


The full data .......................
25th April 2019, ECO mode disabled


Start engine at 0min 02.680sec
Alternator wait for a few seconds of battery discharge before pumping out charge current
At 0min 12.640sec alternator starts charging with peak current up to 68.4 amps and highest
voltage 14.6 volts.


DISCHARGE - Reverse Gear
13.2 volts, -4.9 to -7.5 amps
Start 0min 24.880sec
End 0min 25.440sec Duration approx 3/4 second


DISCHARGE - Reverse Gear
13.1 volts, -3 to -8.0 amps
Start 1min 02.440sec
End 1min 03.240sec Duration approx 3/4 second


DISCHARGE - 2nd gear, crawling speed
13.3 volts, -0.7 to -5.4 amps
Start 1min 18.440sec
End 1min 18.880sec Duration approx 1/2 second


DISCHARGE - 2nd gear, 10KM/H and accelerating slowly to 15 KM/H
13.2 volts, -3.1 to -12.4 amps
Start 2min 26.360sec
End 2min 29.800sec Duration approx 4.5 seconds


ZERO AMPS - 2nd gear, 15KM/H and accelerating slowly to 25 KM/H
13 volts 0 amp
Start 2min 29.800sec
End 2min 37.020sec Duration approx 6.5 seconds


CHARGING ALL THE TIME, variable voltage and amperage
Speed between 10 KM/H to 80 MK/H
Minute 3 to minute 10. Max 30 amps.Average is 25 amps.
Minute 10 to 15, charging from 20 amps to slowly declining to 15 amps
Minute 15 to 20, charging 15 amps slowly declining to 12 amps
Minute 20 to 24, charging 10 amps mostly and at minute 24 under 5 amps.

DISCHARGE - 4th gear 55 KM/h slow de-acceleration or throttle release
13.5 to 13.4 volts, -2.9 to -3.1 amps
Start 24min 53.840sec
End 24min 54.540sec . Duration approx 3/4 second


DISCHARGE - 4th gear 35 KM/h slow de-acceleration or throttle release
13.8 to 13.4 volts, -0.2 to -1.5 amps
Start 25min 06.280sec
End 25min 06.880sec . Duration approx 0.6 second


DISCHARGE - 4th gear 35 KM/h slow de-acceleration or throttle release
13.5 to 13.4 volts, -3.0 to -3.7 amps
Start 25min 10.280sec
End 25min 11.160sec Duration approx 0.9 second


DISCHARGE - 4th gear 38 KM/h slow ACCELERATING
13.3 to 13.4 volts, -0.8 to -3.7 amps
Start 25min 14.380sec
End 25min 14.940sec Duration approx 3/4 second


DISCHARGE - 4th gear 40 KM/h slow de-acceleration or throttle release
13.6 to 13.3 volts, -3.0 to -2.6 amps
Start 25min 30.540sec
End 25min 30.900sec Duration approx 1/2 second


DISCHARGE - 4th gear 35 KM/h slow de-acceleration or throttle release
13.7 to 13.3 volts, -1.1 to -3.4 amps
Start 25min 35.940sec
End 25min 37.160sec Duration approx 1.3 second


DISCHARGE - 4th gear 42 KM/h slow de-acceleration or throttle release
13.5 to 13.3 volts, -0.7 to -3.4 amps
Start 25min 42.880sec
End 25min 43.520sec Duration approx 3/4 second


This very short average 3/4 second discharge and under -7 amps keeps repeating.
At 27min 24sec , 28min 00sec, 28min 12sec, 28min 56sec, 29min 03sec, 29min 07sec,
29min 15sec, 29min 54sec, 30min 32sec , 30 min 43sec, 30min 50sec


NOTABLE LONGER DISCHARGE - speed 15KM/H
13.2V , low -2 amps average discharge
Start 30min 37.200sec
End 30min 40.160sec Duration 3 seconds


NOTABLE LONGER AND MORE POWERFUL DISCHARGE - speed 8KM/H
13.2 volts down to 12.8 volts and amperage was average -30 amps
Start 30min 43.940sec
End 30min 47.940sec Duration 4 seconds


NOTABLE LONGER AND MORE POWERFUL DISCHARGE - Accelerating, speed 15-30 KM/H
Down up to 12.7 volts, amperage up to -35 amps.
Start 31min 18.380sec
End 31min 30.880sec Duration 12.5 seconds


From 31min 31sec alternator was charging. Mostly under 7 amps on average.
Voltage frequently at 13.5 volts, and little time above 14+ volts
Now and then it does that short 3/4 to 1 second discharges.

And then at 41min 47.540sec it does bigger discharge and up to 35 amps
ending at 41min 51.060sec, so only for 3.5 seconds and lowest voltage 12.7volts

And again 1 minute later at 42min 21.180sec to 31.120sec or duration of 9.5 seconds,
it discharged at up to 35 amps and voltage down to 12.8volts.

My video stop at 42minutes 50seconds. Dang !!!

================================================== ===========

How I got the data.
GoPro camera Hero 5 Black. Recording at 2.7K 50 FPS. Mounted on steering wheel housing. Too bad I can't get the RPM due to blockage.
Video file placed on editing software and I place a time code with 1/1000 second. This is the only way I can study frame by frame and see clearly those 0.5 to 3/4 second discharge.

I am showing the video screen capture of this data :

DISCHARGE - 4th gear 35 KM/h slow de-acceleration or throttle release
13.8 to 13.4 volts, -0.2 to -1.5 amps
Start 25min 06.280sec
End 25min 06.880sec Duration approx 0.6 second












NOTABLE LONGER AND MORE POWERFUL DISCHARGE - Accelerating, speed 15-30 KM/H
Down up to 12.7 volts, amperage up to -35 amps.
Start 31min 18.380sec
End 31min 30.880sec Duration 12.5 seconds












Sorry, a very long post.
.

CaliBenzDriver

S-Prihadi, thank you for this short hands-on study.
Based on what this show, it seems quite acceptable results:
- your BATT voltage never went below a normal charged battery range (12.4V...12.7V)
- your alternator never dropped your battery below 11.xV while driving
- currents In or Out did not go super high/low for extended periods

This may not be the whole story!
Keep an eye on Batt Display as you drive around
Play with extended ECO stops until engine restarts while still stopped... (a bunch of high current relays get involved in rear SAM to switch battery loads)

The fact the alternator is electrically able to charge does not mean it does that consistently all the time as expected to maintain batteries.
What I am saying is the hardware (ALT, BATT, Wires, Clamps, Batt-Sensors...) is GOOD but the software in the charging controller (hosted in ME-SFI or CDI) does go randomly nuts and deeply discharge the main battery while driving. I don't believe that 11.9 V drain while driving is by design then 14.9 then back down to 11.9V... super high current swings are battery killers (HEAT): WTF!

FYI: personally I don't count as an actual "Discharge" the (- x) Amps displayed when the alternator dynamically swings voltage down between 14.9V to 12.8V. The current does come out of the battery but the battery voltage stays high enough not to put a dent in actual battery charge.
You rightfully call this SURFACE CHARGE.

How often do you equalize your AGM batteries: Main ; Aux ?

MAIN: Personally ... CTEK monthly or less for cell balancing. If you need to charge often that points to charge fault or a drain (sleepless CanBus module)

AUX: hardly ever because it does not get much abuse during ECO (Engine Cut Off) cycles. AUX always gets initially charged after every start cycle under 14.9V: mostly easy life (AUX junction relay gets the abuse during bypassed feed).

kajtek1

I would consider that another one of those things where technology passed the linguistics.
IMHO they are both the same thing and do the same on different scale.
Is the scale a reason to call them differently?

S-Prihadi

Hi Cali,

Agree that my test is limited to 43 minutes and most importantly I do not ever use ECO at all.
Thus I may not experience ( I hope so ) whatever potential negative points you mentioned on the charging algorithm.

I will never use ECO and I check the AUX battery only once per few months. Its always well charged on its own by its design nature.

My thoughts process for the AUX battery is this :
01. I will only replace it when the dashboard/computer signal a bad AUX battery. Will it ?

02. I will replace AUX battery merely to avoid seeing the bad AUX battery signal,/warning.... nothing more.
I read that the car computer will regularly check AUX battery state of health using internal resistance or something ?
I am sure it will live un-used for 5 years. Today it is almost 5 years already, it is still original to the car since June 2014.

The AUX battery is one area I never took interest on how it actually works or how it will effect charging algorithm, since I will never use it.


"The fact the alternator is electrically able to charge does not mean it does that consistently all the time as expected to maintain batteries."

Agree. When I do long distance run and hopefully the highway not jammed up, I will do more recording of the alternator behavior to know it better.


I don't recondition my batteries, not even those on the boat.
I let it be and replace it when needed. Anyway Varta advised NOT to recond. So I guess I got to trust them.

Later....