I have a sneaky feeling they're somehow involved. The 801D charger charges at 2A and doesn't have these present.
Maha MH-C9000, the Wizard One Charger (Part 2)
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I have a sneaky feeling they're somehow involved. The 801D charger charges at 2A and doesn't have these present.
I still haven't observed voltages above 1.47V on my 0G0E01 unit. The charger shows "done" 1-2 minutes after the voltage reaches 1.47V Charging at rates een 500 amd 1500 mA. Cells are AA 1700, 2100 and 2000 All Sanyo old school and Eneloop. AAAs are 750 and 800 old school and Eneloops.
So far, from my obervations, I have no reason to believe that this batch (0G0E01) terminates on other than maxV of 1.47V. I guess there is a -dV onboard but a charger with multiple safety features utilizes whatever comes first to terminate the charge. In my case, maxV is reached before -dV, simply because maxV is set a bit too low.
I would invite all owners of c9000 units with 0G0E01 serial numbers to observe the peak voltage of their cells. Please mind that this should be the voltage displayed just before done. In some cases, during topoff the voltage can exceed 1.47V. For instance with AA cells towards the end of the topoff the voltage reaches 1.49V and with AAA it is 1.50V.
On the positive side, using this termination my cells stay cool at any charge rate I've used. If I leave them to topoff for 2 hours, I reach about 95% charge completeness with AA cells and 100% with AAA (16 hours at 0.1C sets the 100% mark).
SilverFox
Flashaholic
Hello NiOOH,
While your observations are interesting, there are several people who have observed contrary results. I have a lot of cells that terminate at 1.47 volts, but others that go both higher and lower.
Also, I have it on good authority that only one change was made to the C-9000 firmware and that the changes in the serial numbers only refer to lot numbers. 0F was the original model. All units after that should perform the same, since there has been no other improvements. I believe the improvement was made early in February 2007.
I should also point out that I have observed my Schulze terminating at around 1.47 volts per cell when charging some of my battery packs.
Perhaps there is just something about 1.47 volts...
Tom
While your observations are interesting, there are several people who have observed contrary results. I have a lot of cells that terminate at 1.47 volts, but others that go both higher and lower.
Also, I have it on good authority that only one change was made to the C-9000 firmware and that the changes in the serial numbers only refer to lot numbers. 0F was the original model. All units after that should perform the same, since there has been no other improvements. I believe the improvement was made early in February 2007.
I should also point out that I have observed my Schulze terminating at around 1.47 volts per cell when charging some of my battery packs.
Perhaps there is just something about 1.47 volts...
Tom
TorchBoy
Flashlight Enthusiast
So what are your thoughts about the claims that another bug has been removed in OGOE01?
Yes. Unless you can't be bothered waiting that extra time, or in coming back. They'll still work, just for slightly shorter.
Hello Tom.
I doubt that 1.47 V is THE magic number
I can say that 1.47 V is NOT the peak voltage. As I wrote before, during top-off charge the cells voltage exceeds this value. This leaves me with the strong impression that the charger uses maxV. Now, I could imagine that the maxV value could be somehow connected to the internal resistance of the cell. It is known that cells with higher IR reach higher voltages during charging. It could be that the the charger calculates the value of maxV according to the value of IR from the initial check. My cells are in fairly good shape. For my AAs, I get values from 1.47V to 1.65V during this check. If someone has cells with higher IR that test to about 2.0V when inserted in the c9000 it would be interesting to compare the maxV at the end of charge.
SilverFox
Flashaholic
Hello Ian,
Let me see if I can find an answer to that... I just got a new unit and will have to run some tests to see if it repeats digits on slot 1 during cycling.
Tom
Let me see if I can find an answer to that... I just got a new unit and will have to run some tests to see if it repeats digits on slot 1 during cycling.
Tom
SilverFox
Flashaholic
Hello NiOOH,
I believe the C-9000 uses peak voltage, or a very small -dV for termination. As I understand it, there is a maximum voltage cut off, but it is around 1.8 - 2.0 volts and is set to prevent you from charging Alkaline cells, should they get by the IR test.
Cells with higher IR will charge to a higher voltage, so we may be able to get a handle on the 1.47 volt number by also observing the IR check number when the cell is first inserted. The problem is that I am not sure what the IR number is. I believe several checks are done, and the number that is displayed is the results of one of those numbers. I am just not sure how that number figures into things.
Tom
I believe the C-9000 uses peak voltage, or a very small -dV for termination. As I understand it, there is a maximum voltage cut off, but it is around 1.8 - 2.0 volts and is set to prevent you from charging Alkaline cells, should they get by the IR test.
Cells with higher IR will charge to a higher voltage, so we may be able to get a handle on the 1.47 volt number by also observing the IR check number when the cell is first inserted. The problem is that I am not sure what the IR number is. I believe several checks are done, and the number that is displayed is the results of one of those numbers. I am just not sure how that number figures into things.
Tom
Another one :naughty:! Congrats on the new purchase.
What is the serial number on that one?
I am still interested on the maxV issue.
varuscelli
Flashlight Enthusiast
Just to briefly compare notes on models received, I ordered a C9000 from Thomas Distributing on Sept 15 and received the 0G0B01 version.
rizky_p
Flashlight Enthusiast
I have an old firmware C9000 which i bought few months back, i experience several problems that people here are mentioning regarding first firmware such as charge indefinetely(missed charge termination) with below 0.5C but other that all is fine. the question is does the first firmware do the top-off/tricle charge charge after full charge? cause i heard that one of the problem with early firmware it didnt actually doing a tricle charge.
thanks
thanks
Power Me Up
Enlightened
I'm pretty sure that the original C9000 does do a trickle charge after the main charge is completed. Trickle charge on both revisions of the C9000 should be a modulated pulse charge which averages to 10mA.
Because of the changes to the charge termination algorithm with the new revision, cells aren't fully charged at the end of the main charge and so the new revisions of the C9000 performs a 100mA top off charge for 2 hours after the main charge is complete. After that, it then goes to trickle charge mode.
The trickle charge isn't there to bring up the capacity any further - it's just done to counteract any self discharge that the cell would otherwise undergo.
I will get one of these, thanks all for your info and comments. It would be nice if it had a usb or serial port to be able to set the exact charge current (currently the specs say you can only do .2 increments on the charge current) and other more detailed/manual settings.
Will we see deals for the Holidays! Hint Hint
Will we see deals for the Holidays! Hint Hint
Power Me Up
Enlightened
I will get one of these, thanks all for your info and comments. It would be nice if it had a usb or serial port to be able to set the exact charge current (currently the specs say you can only do .2 increments on the charge current) and other more detailed/manual settings.
Will we see deals for the Holidays! Hint Hint
You can actually set the charge current in 100 mA increments (from 200 mA up to 2000 mA)
I agree that a charger with a USB or serial port would be good - although I'd want it for data logging purposes rather than being able to have precise control of charging rates.
MrAl is working on a chip for building a computer controlled DIY charger/tester:
https://www.candlepowerforums.com/threads/175281
The version he's currently working on won't be able to select the charge/discharge rates at all, but a future version might be able to.
Thank you Power Me Up, very interesting!
bcwang
Enlightened
I recently got an RMA replacement for my c9000 and it is 0G0IA. It doesn't follow the normal batch number convention at all. It is also a black label now instead of white. I wonder if this is extremely new or just different being an RMA unit. I did test charging on both of my units at 500mah with fully charged 2500mah cells and they all terminated quickly. No more fear of burning batteries yay!
Power Me Up
Enlightened
It'll be interesting to see if anyone else gets a new unit with that code on it.
Do you know how to reproduce the repeating digits bug? Could you have a go and see if the replacement unit still has that bug?
Question "Power Me Up?"
the specs say;
the specs say;
- 10 Selectable Charging Currents: 0.2A, 0.4A, 0.6A, 0.8A, 1.0A, 1.2A, 1.4A, 1.6A, 1.8A, 2.0A ( 2.0A is the same as 2000mA, 0.2A same as 200mA, etc..)
- 10 Selectable Discharging Currents: 0.1A, 0.2A, 0.3A, 0.4A, 0.5A, 0.6A, 0.7A, 0.8A, 0.9A, 1.0A
- which shows ".2" -Charging- increments but you say it does 100 mA increments! (you have it, I don't) the reason I ask is eneloops say they work best at .7 charging and I wanted to do it at that. Thx
Power Me Up
Enlightened
Yep - it definitely allows charging in 100 mA increments. The current specifications on the Maha web site also reflect this:
http://www.mahaenergy.com/store/viewItem.asp?idProduct=423&cur=specs#mid
That page does show the discharge termination incorrectly as 1.00 Volts - the current version terminates the discharge at 0.90 Volts under load - the first version terminated discharge at 1.00 Volts open circuit.
As far as charging Eneloops go, I use the default 1000 mA charge rate without any problems. As reported many times by Silverfox, most battery manufacturers recommend charging in the 0.5C to 1.0C range (1000 mA to 2000 mA for AA Eneloops) when doing fast charging. Charging at 700 mA works out to be 0.35C which is not recommended due to the fact that it will give a reduced end of charge signal which can cause the cell to be overcharged and damaged. Probably won't be a problem for some time while the cells are still new and are giving a good end of charge signal, but it might become a problem in the future as the cells age.
