Test/Review of Charger SkyRC MC3000

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ferongr
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I’m interested in answers in some of these questions too (the program number issue for example and the USB coding) since I’ve been looking at the charger from time to time.

What I know is that most people use Data Explorer instead of SkyRC’s software and that Bluetooth is considered a lost cause, but mostly due to the bad app. There has been a redesign of the case and and also a switch in suppliers so it’s a lot stronger now.

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I will eventually buy one. But not until the issues brought up by members here are addressed.

I have QC issues with SkyRC. And they have no USA based warranty support. Here is some info on another of their products…the B6 mini……

Here is a graphic example of why I’m very skeptical of SkyRC products. They seem to lack in design skills.
Here is an Authentic SkyRC B6 Mini. You can see the USB port. Notice that the PC board holding the USB port is somewhat of a peninsula (or finger) sticking out with the USB port at the end. What happens is that it takes VERY little pressure while inserting and removing the USB plug to cause this fragile part of the PC board to flex slightly each time you connect or disconnect the USB cable. In very short order, the solder connections crack because the board flexes, leaving the USB port inoperative.

It’s this kind of dumb engineering (or lack of) that give me very little confidence in SkyRC products. That combined with no USA based place to get warranty service. Not to mention all the reports of MC3000 problems here on this forum.

The points marked in red are the fragile points that break easily as the board flexes. There really is no excuse for this kind of design foopahs.
It doesn’t take an engineer to see that putting the USB port on a flexible part of the PC board like this is inexcusable and does not instill product confidence imo.

My advice with these is to get a dedicated USB cable, plug it in ONCE, and leave it plugged into the B6 mini. Only unplug it from the Computer.

Tom E
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I have to agree bout this company. Great features/function, much less attention to production engineering, packaging, etc. However I must say SkyRC was very responsive to me from contacting them on their website, though they deferred to GearBest for the replacement cover.

Ohhh - finally after long delays, I got a replacement cover for the MC3000 from GearBest!! Well, typical for GearBest, the packing of such a light plastic housing was totally wrong, bad, sloppy, cheap --- I'd use more descriptions but think you get the picture. Even though it was in a thin plastic bag in the standard cheapo very thin bubble wrap lined bag, I though it survived but noticed a small piece of plastic in the bag, and of course it's a piece broken off the tip of one of the spring tab/studs -- the exact reason why I ordered/needed a replacement!

Looking it over, the 4 spring tabs/studs are the only thing sticking out from the housing, so of course are susceptible to being broken off when nothing is protecting it from getting banged around in shipping.

 

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Tom E wrote:

Looking it over, the 4 spring tabs/studs are the only thing sticking out from the housing, so of course are susceptible to being broken off when nothing is protecting it from getting banged around in shipping.


 


Perhaps thats the real inspiration for the store named Banggood Big Smile

The Journal of Alternative Facts TM

"It is critical that there is a credible academic source for the growing and important discipline of alternative facts. This field of study will just keep winning, and we knew that all the best people would want to be on board. There is a real risk in the world today that people might be getting their information about science from actual scientists"

 

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Tom,
I’m not exactly sure what type plastic the housings are made from but you might look into Weld-On plastic adhesives for repair. If the plastic breaks that easily I doubt it’s ABS, maybe Polypropylene.

I use Weld-On for a lot of plastic repairs and they are usually as strong (or stronger) than the original part.

SkyRC (IMO), has very poor engineering and design. As mentioned above, the mistakes they make are simply inexcusable.
They may have good EE designs, but the physical designs of their PC boards and housings is poor to awful. (again, imo)

It’s THE reason I have not purchased an MC3000. Well, that and lack of after sale support…and a shopping list of user suggested improvements that members here have pointed out need to be made…..and have not yet.

It’s also the reason I continue to pursue using a Data Logger with my B6 mini and Accucell.

Not sure if the Xtar Dragon has this capability (exporting Data).

Zebretta
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Bort wrote:
Tom E wrote:
Looking it over, the 4 spring tabs/studs are the only thing sticking out from the housing, so of course are susceptible to being broken off when nothing is protecting it from getting banged around in shipping.  
Perhaps thats the real inspiration for the store named Banggood Big Smile

Probably has to do with something getting lost in the translation and they thought English speaking people would like getting a lot of “Bang” for the Buck”?

But “GoodBangForTheBuck” didn’t sound right.

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I used an epoxy glue to re-attach the broken stem from shipping. I'm trying to assemble it, but it's a freak'n nightmare - no instructions, the 4 sliders to get into position is totally, insanely nuts!

It's sitting there on my bench in pieces, and I don't have faith the stem will hold up when all back together. Been way too bizy to spend that kind of time this needs. Hope to get back to it soon.

Zebretta
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Tom E wrote:

I used an epoxy glue to re-attach the broken stem from shipping. I’m trying to assemble it, but it’s a freak’n nightmare – no instructions, the 4 sliders to get into position is totally, insanely nuts!


It’s sitting there on my bench in pieces, and I don’t have faith the stem will hold up when all back together. Been way too bizy to spend that kind of time this needs. Hope to get back to it soon.

Any chance you could post a photo of your repair and the innards you’re trying to reassemble before closing it up?
I think many others have had (or will eventually have) this same problem.

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Zebretta wrote:
and a shopping list of user suggested improvements that members here have pointed out need to be made…..and have not yet.

A very long list of improvements has been implemented on the charger, what do you believe is missing?

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

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Zebretta wrote:
Tom,
I’m not exactly sure what type plastic the housings are made from but you might look into Weld-On plastic adhesives for repair. If the plastic breaks that easily I doubt it’s ABS, maybe Polypropylene.

I use Weld-On for a lot of plastic repairs and they are usually as strong (or stronger) than the original part.

SkyRC (IMO), has very poor engineering and design. As mentioned above, the mistakes they make are simply inexcusable.
They may have good EE designs, but the physical designs of their PC boards and housings is poor to awful. (again, imo)

It’s THE reason I have not purchased an MC3000. Well, that and lack of after sale support…and a shopping list of user suggested improvements that members here have pointed out need to be made…..and have not yet.

It’s also the reason I continue to pursue using a Data Logger with my B6 mini and Accucell.

Not sure if the Xtar Dragon has this capability (exporting Data).

What you said is my thoughts exactly. I’ll never buy anything from this company.

Boycott Nike

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gauss163 wrote:
SkyRC is not alone in having problems with the plastics employed, e.g. recall the XTAR VP2 recall due to “brittle” plastic housing. Yet $14 competitors like the Liitokala Lii-500 seem to have no analogous plastic problems. The mind boggles…. Don’t beleive the (marketing) hype.

At least Xtar recalled the VP2 when the problem was discovered. From what I’ve read about SkyRC, their customer support sucks.

Boycott Nike

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gauss163 wrote:
atbglenn wrote:
At least Xtar recalled the VP2 when the problem was discovered. From what I’ve read about SkyRC, their customer support sucks.

But XTAR didn’t recall the much more serious WP2s meltdowns. Caveat emptor.

True, but the WP2 cost 5 times less than a MC3000. BTW, I’ve owned 10 Xtar’s including 2 of the first gen WP2’s and never had problems with any of them. I’ve since given my WP2’s away to friends and they’re still working 5 years later.

Boycott Nike

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Here's the original case:

Here's the replacement case that had a stem snapped off, and with the stem repaired with a supposed good epoxy glue:

Here's the mess:

I looked it over again and can't begin to understand how it's possible to work in this space and get everything aligned up perfectly. Nothing fits snugly.

They glued the connectors with really tough stuff so can't work on it in pieces. I got all the buttons, display and boards moved over ok, I'm just stuck on aligning/assembling the sliders.

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K, think (thought) I found a way to assemble it. For the 6 screws securing down the back cover, I had only 5. For some reason couldn't get them to tighten the case completely - just a hiar worth of looseness. Tried it anyway - oh boy... One of those long slots popped out, angled now in the case - of course I tried this with a cell and power, so.... The charger reset, and then noticed the distinct smell of burning electronics. Turned it off. I straightened out the slot, and this time held the case tightly together and the screw actually tightened it all up. So it's working - but on only 2 slots - the 3rd and 4th. 1st and 2nd are dead - don't recognize a battery, so sure something critical went up in smoke for those 2 slots. So I'm worse then when I started - I had only one dead slot, now I got 2 dead ones.

Now that I know how to assemble it, might have to take a looksy to see if I can see what burnt, and if it's replaceable. Or buy a new one? Really wanted to charge 4 cells at a time with this - got lots of SRK style lights now...

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I also had trouble putting the MC3000 together after fixing a broken post. In the process the whole thing stopped working when one of the rails slipped and probably shorted something. Just like you couldn’t close the case all the way. Got an error message about the ADC after getting it sorted.

There’s isn’t anything similar on the market so just bought a third one. At least now both of them have the new case with better posts.

Zebretta
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HKJ wrote:
Zebretta wrote:
and a shopping list of user suggested improvements that members here have pointed out need to be made…..and have not yet.

A very long list of improvements has been implemented on the charger, what do you believe is missing?

Here is the list that members came up with……..The thread died so I didn’t see where these were resolved. Maybe in another thread?

  • It is required to remember the program numbers or press a key, on the initial screen there is no hint on how the selected program works.
  • Default time on LiIon is 3 hours, this is to short.
  • When terminating on time or capacity, no capacity information is saved.
  • Break_in shows charged capacity, not discharge capacity.
  • Backlight always requires a keypress to turn on, putting a battery into the charger will not turn the light on
  • Factory calibration do not match specifications.
  • The PC software requires a high screen resolution
  • NiMH charge curves looks messy on PC, an option to hiding measuring pauses would be nice.
  • PC software saves csv files at wrong location.
  • It is not possible to copy programming from one charger to another, people with more than one charger (That will be me) must enter each program on each charger!
  • The Bluetooth software is not stable and do not work on all phones.
  • Strange coding on the usb output, why not use a chip to automatic get the best coding?
HKJ
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Some of them is preferences not bugs and many of them has been fixed.

The master list of bugs and fixes is in post #6 in this thread:
http://www.candlepowerforums.com/vb/showthread.php?389700-SkyRC-%97-IFA-2014-%97-MC3000-charger-analyzer

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

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Perhaps it will be simpler if the “unfixed” issues are enumerated here?

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Tom,
Thanks for the photos. A picture is worth 1000 words and now I see exactly what you’re up against.

Maybe they’ve since corrected all the issues with the MC3000. I don’t know. I wonder if there’s a photo here somewhere of the new post design.

I sorely miss “Made In America”. If a charger that offered those same features and was made in the USA….heck I’d spend twice as much because I know the warranty would be honored and that means the quality would be better to begin with. The actual price we pay for “cheap” Chinese goods is expensive.

So you’re going to possibly just buy another as a fix…maybe a fix…..maybe another lemon?

Unfortunately, to get those expensive “cheap” goods, we’ve abandoned our ability to make much of anything domestically and every component would have to come from guess where? Ultimately expensive, “cheap” Chinese goods are an opiate on which the world is addicted…to it’s own demise.

Zebretta
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HKJ wrote:
Some of them is preferences not bugs and many of them has been fixed.

The master list of bugs and fixes is in post #6 in this thread:
http://www.candlepowerforums.com/vb/showthread.php?389700-SkyRC-%97-IFA-2014-%97-MC3000-charger-analyzer

A quick look through the list didn’t reveal (to my tired eyes) a fix for the all important and critical breaking post issue?
Did I miss it?

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maukka wrote:
I also had trouble putting the MC3000 together after fixing a broken post. In the process the whole thing stopped working when one of the rails slipped and probably shorted something. Just like you couldn’t close the case all the way. Got an error message about the ADC after getting it sorted.

There’s isn’t anything similar on the market so just bought a third one. Facepalm

How do you know the new ones have better posts? Did you take it apart or can you see them without disassembly?
Is there a photo of the new posts on the forum somewhere?

HKJ
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Zebretta wrote:
HKJ wrote:
Some of them is preferences not bugs and many of them has been fixed.

The master list of bugs and fixes is in post #6 in this thread:
http://www.candlepowerforums.com/vb/showthread.php?389700-SkyRC-%97-IFA-2014-%97-MC3000-charger-analyzer

A quick look through the list didn’t reveal (to my tired eyes) a fix for the all important and critical breaking post issue?
Did I miss it?

I was fixed a long time ago.

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Zebretta
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HKJ wrote:
Zebretta wrote:
HKJ wrote:
Some of them is preferences not bugs and many of them has been fixed.

The master list of bugs and fixes is in post #6 in this thread:
http://www.candlepowerforums.com/vb/showthread.php?389700-SkyRC-%97-IFA-2014-%97-MC3000-charger-analyzer

A quick look through the list didn’t reveal (to my tired eyes) a fix for the all important and critical breaking post issue?
Did I miss it?

I was fixed a long time ago.

ok. It’s hard to figure out the timeline of some of the fixes and I didn’t see it in the list.

That’s good to know. But wait….in the posts above, TomE just this week says he received a replacement cover for one that had broken pins and it ALSO has the same issue?

Tom E wrote:
and of course it’s a piece broken off the tip of one of the spring tab/studs — the exact reason why I ordered/needed a replacement!

Maybe the post were stronger, but still broken due to shipping? This is confusing. Facepalm

So I wonder if ALL the discovered bugs and problems have been resolved now or if there are any new ones that have not yet.

Tom E
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Oh, sorry. The problem with the case was a batch was made with poor brittle plastic that caused the posts to break.  I should take pics of the old vs. new, but the new case does have better made posts - better, stronger support base of the post, but also should be made of the better material. The problems with the replacement case was a post broke in shipping because GearBest (and the source vendor - SkyRC?) packed it incredibly stupidly.

So HKJ is right - this post problem was fixed long ago. I bought mine from GearBest, of course we know not the best vendor, but the best price of course. Another issue was I had mine for a few months before I even turned it on for the first time, so when all this started for me, the new better batches have been out there for a while.

I ordered the case replacement on Dec 24, 2016, and ordered the charger on Aug 16, 2016. I believe the better case were shipped before August, but GearBest/SkyRC apparently didn't do a "recall" to pull "bad" units off the shelves, so old inventory still was shipping, and by the time I ordered the bare case, they were out of stock

Maukka - you don't know how happy I am you had the same exact problem, and you are totally correct bout there's nothing else like it. $90 now at GearBest, $10 less than I paid - think'n bout it.

I should add, SkyRC did respond well to my email to their support. I was happy with their responses, and thought they were considerate. I never did bother contacting them though after receiving the broken replacement - my bad. Here's the first response:

 


 

From: SkyRC_Karl Peng [mailto:karl@skyrc.cn]

Sent: Monday, February 6, 2017 9:11 PM

To: Tom E

Subject: Re: MC3000 questions...

 

Hello Tom Elfers,

thanks for contacting SKYRC.

We are very sorry to hear about the plastic material failure which you experienced with your first unit of MC3000 from Gearbest. We are glad to hear that you are already in the GB process of warranty service. The replacement part will fit your charger, has an improved construction design and also is built with much higher quality plastic material. You can find documentation about this improved replacement part on CPF, the flashlight forum.

 

Are you saying that GB has run out of stock of the replacement part? — Let me check and take care of it. Everyone in China has been on 2-4 weeks CNY holiday season vacation, that is another reason for the unusual delay in the process, sorry for the long wait.

Good luck with the GB warrant service process,

hope you can get the improved part soon,

please don't be disappointed,

best regards

 

Important Notice: In order to prevent financial fraud, if you get the notice of changing bank account, please confirm if there is an official email of "Bank Account Change Notice" with SkyRC company stamp and signature. And if you still have questions, please feel free to contact SkyRC via SkyRC official tel+86-0755-83860222 for reconfirmation. Thank you.

Karl Peng Sales Department SkyRC Technology Co., Ltd. 4/F, Building No.6, Meitai Industry Park, Guanguang South Road, Guihua, Guanlan, Longhua New District, Shenzhen 518110, China T: 0755-83860222-806 F: 0755-81702090 M: 18476631970 Email: karl@skyrc.cn www.skyrc.com

   

This email is confidential and intended solely for the use of the individual to whom it is addressed. Any views or opinions presented are solely those of the author and do not necessarily represent those of SkyRC Technology Co., Ltd. If you are not the intended recipient, be advised that you have received this email in error and that any use, dissemination, forwarding, printing or copying of this email is strictly prohibited. If you have received this email in error please contact the sender.

 

From: Tom E

Date: 2017-02-06 10:52

To: info@skyrc.cn

Subject: MC3000 questions...

Hi,

I bought an MC3000 from GearBest, and after just a couple weeks of use, the left most bay’s spring popped off. Took off the cover and noticed the plastic pin snapped on the left most bay, and the right most bay’s pin holding the spring is also broken, and won’t last long.

I ordered a replacement case from GearBest for $20, and have been waiting for weeks for it to come in stock.

Is there anything you can do to expedite the replacement? After all, it’s a defect in manufacturing or design – not my fault, not GearBest’s fault. Also is there anything you can tell me about the replacement case? GearBest is not capable of answering my questions. My main concern is will this replacement case fit my unit, and is it an improved design?

Please, please, help – please, if you can, at least, answer my questions.

 I’m a very disappointed customer – I expect better quality for this kind of money. For such high level features and advanced functionality, I would expect better attention to details of quality.

Thanks!

Tom E

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Tom E wrote:

K, think (thought) I found a way to assemble it. For the 6 screws securing down the back cover, I had only 5. For some reason couldn’t get them to tighten the case completely – just a hiar worth of looseness. Tried it anyway – oh boy… One of those long slots popped out, angled now in the case – of course I tried this with a cell and power, so…. The charger reset, and then noticed the distinct smell of burning electronics. Turned it off. I straightened out the slot, and this time held the case tightly together and the screw actually tightened it all up. So it’s working – but on only 2 slots – the 3rd and 4th. 1st and 2nd are dead – don’t recognize a battery, so sure something critical went up in smoke for those 2 slots. So I’m worse then when I started – I had only one dead slot, now I got 2 dead ones.


Now that I know how to assemble it, might have to take a looksy to see if I can see what burnt, and if it’s replaceable. Or buy a new one? Really wanted to charge 4 cells at a time with this – got lots of SRK style lights now…

Ouch!

This is my concern. I guess I’m lucky that mine hasn’t had any of the posts break (ordered December 2015). Having heard of this issue, I’ve been rather careful with the sliders, and perhaps that helps. The dilemma is what to do when it breaks. The top cover has been in my shopping cart for a while now, but i’m concerned that I might run into trouble putting it back together, as this has been reported quite a few times.

The sticking point is that the bloody top cover is expensive. At $20.00, it is nearly a quarter (22.22%) of the cost of a new charger (currently $89.99)! Unfortunately, there really isn’t anything else like it (despite my hopes when I first heard of the Xtar Dragon), so if it breaks I’ll likely get a replacement. If I buy the top cover, screw up putting it back together, then get a replacement charger, I’d be $109.99 poorer (instead of just $89.99).

Tom E
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I got a 2 cell MC3000 charger now, and ordered another MC3000 at discount for $90, so it's on the way frowncry

I got $20 credit from Gearbest which I used to buy the cover - funny because I had 2 slots working before, and 2 slots now, but for different reasons.

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EXPERIENCE BY REPAIRING MC3000 AND EXPLANATION OF ITS MEASURING METHOD.

Many things have been written about repairing the hardware of MC3000.
This is a hands on repairing of the electronics and something about its inner basic functioning with block diagram – drawing maybe later Smile

I hope some members with experience or interrest in electronics and a MC3000 can benefit from this. It will be rather technical so you are warned.

First the repaired errors:
error 1: Slot 1 and 2 not working, 5V regulator burning hot.
Reason:
The metal rail for slot #2 was loose (prob. because the plastic support, middle, was broken), moved a bit and made a short to the AD-circuit with IC16 (MCP3424) that got a defect and drew excessive current.
I cut the +5V pin on IC16 and the uP now would not start up as the I2C-bus did not answer from IC16.
Remedy:
Exchanged IC16 with MCP3424E-SL from AliExpress ($3.5)

error 2:
True charge- and discharge-currents wrong (one too big and one too small, worst at higher voltages (LiIon)).
Reason:
Probably small short-circuits and reverse battery insertion (carelessness).
slot#3: Leakage in zeener diode type ZM4734 (5.6V), in clipper circuit just before input to the AD-converter IC15.pin1. Measured -7.1mV on pin1 (normally -0.3mV), thus a 6.8 mV error (unbalance).
The AD-converter interprets 1 mV differential as 0.040A (measured), so now it measured discharge 6.8 × 40 = 272 mA too high and charge 272 mA too low. The uP reacts by turning the discharge current 272 mA lower than setting and charge current 272 mA higher than setting. This cannot be seen on the display! (see explanation below).
slot#2: Small leakage in zeener diode type ZM4734 (5.6V), before input to the AD-converter IC16.pin11. Gave -0.5 mV on pin 11 (‘+’ input, normaly -0.3mV), thus a 0.2mV unbalance. This gave a charge/discharge error of 8/-8 mA.
Remedy: The two zeener diodes were replaced with selected-for-low-leakage zeeners (6.2V, as 5.6V ones had too high leakage).
Result: Still a very small error in slot#2.
ToDo: Replace with Semtech ZM4734, ordered on ebay.

EDIT: ZM4734 was too big (size LL41-5 mm) so I have ordered” ZMM5V6 (size LL34-3.5mm) instead.”:http://www.ebay.com/itm/100PCS-Zener-diode-ZMM5V6-5-6V-1-2W-5V6-LL34/291...

DESCRIPTION OF THE BLOCK DIAGRAM:
The MC3000 is build around a 0.025 Ohm resistor to measure the current to/from the battery. Figure this is connected with plus to the bottom of the resistor and with minus to ground.
On the top of the resistor is a discharge FET IRF3205 to ground and a DC-DC switch circuit that convert +15V to battery charge voltage by means of pulses from the uP (not at the same time as discharge, of course).

Discharge:
An 18 bit AD converter MCP3424E-SL (only 14 bits used, I think) measures differentially the voltage drop over the resistor (through a LP filter and security clipper circuit) and the uP fetches the measured voltage by I2C-bus and calculates the current. 10 mV corresponds to 400 mA. That very low voltage makes the measurement very sensible to leakage current (as told above).
The uP then compares the measurement with the set (wanted) current and outputs a corrected PWM signal at 20 KHz, filtered to DC through a RC filter. This voltage is fed to an integrating (slow start) driver for the discharge FET. Pulse width of PWM signal is around 6us for 400mA and the filtered DC is around 390 mV.

Charge:
The uP sends adequate negative pulses to a P-channel FET 4407A that pushes current from the 15V rail into a big coil in the DC-DC converter which output is the top of the 0.025 Ohm resistor. The current is measured by the uP via the AD converter so that the uP can correct the current through the pulses to FET 4407A.

Functioning of the display at Discharge/Charge in case of miscalibration or leakage error as in ‘error 2’:
1. The current shown under CURR is not the true current.
2. mAh is derived from the current shown under CURR, not the true current.

This means that if there is an offset in the measuring circuit (as above, in error 2), the current will be measured (and corrected) wrongly and mAh will be in error and you cannot tell from the display that anything is wrong.
e.g. The true charge current could be 1.8A when set to 1A and the Capacity cut-off would be in error or even missing at charging, or Capacity cut-off could happen without any current was drained from the battery.
In any case the use of voltage cut-off at both charging and discharging will give a good security, but cannot protect against excessive charge or discharge currents. I advice to check currents at intervals with a Amp-meter. The true current can also be checked by starting the calibration procedure on MC3000.

Tom E
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Wow, might just try the error #1 fix. Great work and info!!

tempo
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sixty545 wrote:
2. mAh is derived from the chosen, not the true, current.

Thanks for your analysis!! But if i choose 3000mA charge rate, the mAh should be a straight line in the graph at the beginning y=mx+b. But can you provide a graph from the PC software?

The mAh graph is curved at the beginning when the current ramps up, it takes a few seconds to reach 3000mA no? The curved graph tells me that mAh is derived from the true current, or are you wrong?

Tom E
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Ordered the MCP3424E-SL from here: https://www.aliexpress.com/item/18-MCP3424-E-SL for $3.35 USD

 

 

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