Maha MH-C9000 SUPPORT / FAQ - continuation

[Yamabushi]

Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!

i have 6 different size batteries and none of them are AA or AAA.

I have to ask ... other than C and D, what other sizes of 1.2 V NiMH do you have and what devices use them?

 

[donn_]

Does the 9000 default to 1A charge, no matter what size cell is put in it?

 

[N8N]

yes, all it knows is whether a cell is present and it detects somehow NiMH or NiCd. Other than that you have to tell it what to do.

 

[donn_]

Thanks.

Another flaw in an almost perfect charger.

 

[papershredder]

Thanks.

Another flaw in an almost perfect charger.

Yeah, I don't know what they were thinking?
My power went out for half of a second the other day, which happens rarely where I live.

Two things I had to deal with:

Motor in AC unit started acting up until I gave it a proper power cycle. It was making some weird noises.
Maha C9000 charger decided it was time to charge. :shakehead

 

[N8N]

The latter I deal with by leaving it plugged into a UPS... which reminds me, I need to box it up & send it back, the wall wart died anyway

Sent from my XT897 using Tapatalk 4

 

[N8N]

Discovered something today. Got my replacement C9000 in the mail which is good because I had some cells that I'd actually run out of juice and needed to charge, and also I bought some more. Among the "more" that I bought were two Tenergy D cells, which are rated at 8000 mAh. They're breaking in right now, and I discovered something... they'll charge at 0.1C fine (800mA) but they are discharging at only 1A - whereas 0.2C would be 1600 mA. I guess the maximum discharge current of these things must be 1A so anything over 5000 mAh will take even longer than the usual 39 hours to break in! Not sure how the lower discharge current will affect the capacity reading, I guess I would assume that it would artificially inflate it. Certainly using the C9000 on C or D cells regularly would be quite the PITA, I'm looking for another charger that will handle them for regular charging, but then again I don't need a whole lot of the larger sized cells.

I was a little disappointed, there wasn't a whole lot of charge left in these cells per the pre-break in discharge, only around 2000 mAh. Couldn't see a date on them either though. I'll take 'em back if they don't test in spec though.

Edit: they must have just sat around for ages and ages and might not have been charged up fully from the factory... I started them at different times as one of them discharged first and I only need one for immediate use; that one has discharged 4500 mAh and still decent voltage. I'll try to remember to test the charge in the one that I won't be using if I haven't found a home for it in 3 months or so.

 

[Mr Happy]

they are discharging at only 1A - whereas 0.2C would be 1600 mA.

The C9000 has a maximum charge current of 2000 mA and a maximum discharge current of 1000 mA.

 

[DarkMorford]

Hi, all! I ordered my MH-C9000 from Amazon back in April (it's the 0L0HA revision), and immediately started running all my batteries through it, weeding out all the ones that were too far gone to keep a charge anymore. It worked great, and I absolutely loved it!

I've only used it on and off since then, but about a month ago I noticed it being reluctant to charge more than one cell at once. I went out and bought some brand-new batteries (Sony CycleEnergy 2500 mAh AA cells), and while the C9000 will happily charge one at a time, as soon as I insert a second battery and select the charge cycle—using the default 1000 mA charge rate—the thing resets and tries to start over. It then continues resetting itself non-stop until I take one of the cells out. It goes without saying that 3 or 4 cells produces the same behavior.

Did I just end up with a bum charger? Is there any way to fix this?

 

[Power Me Up]

It could be that the power supply is failing. If you've got access to another power supply that provides a regulated 12V output and the same plug and polarity, you could try it with that.

A few questions:

Does it work with any single slot charging? Does it work if you select a 2000 mA charging rate?

 

[N8N]

I ordered mine in early May, same rev, and my power supply completely died between one use and the next (probably a week or two.)

Do you have a meter and can you measure the output of the wall wart?

Also, if you have the cig lighter adapter you could try that too. In fact I am thinking of ditching the wart and wiring a harness straight from the battery expansion connector of my UPS to the power plug on the C9000 that way less loss and more reliability... since I have to have it plugged into the UPS anyway it only makes sense

 

[DarkMorford]

Unfortunately, I do not have another compatible power supply, either AC or DC. The supply I have measures exactly 12 V unloaded, but I don't have a way to measure it under load. Any of the four charging lanes work, but ratcheting the charger up to a full 2000 mA charging rate causes it to reset itself.

Starting to sound to me like it is the supply, but I don't know how to test it for sure.

 

[Planz]

Does the 9000 default to 1A charge, no matter what size cell is put in it?

That is one of the irritating aspect of the Maha.
They have serious competition now and this will drive them to update their design.

http://www.candlepowerforums.com/vb/showthread.php?366538-Anyone-have-the-SkyRC-NC2500-charger

 

[Power Me Up]

Unfortunately, I do not have another compatible power supply, either AC or DC. The supply I have measures exactly 12 V unloaded, but I don't have a way to measure it under load. Any of the four charging lanes work, but ratcheting the charger up to a full 2000 mA charging rate causes it to reset itself.

Starting to sound to me like it is the supply, but I don't know how to test it for sure.

Definitely sounds like the power supply to me.

Try calling Maha directly - they're pretty good with their after sales service!

 

[NeoLoop]

Hi, all! I ordered my MH-C9000 from Amazon back in April (it's the 0L0HA revision), and immediately started running all my batteries through it, weeding out all the ones that were too far gone to keep a charge anymore. It worked great, and I absolutely loved it!

Hi all n hi DarkMorford,
where i can see the production code version (revision), is that on the box or in the unit ?

is anyone can help me to post the picture here, to show me where side I can find n see the code version of MHC-9000, so i can make sure buy the recent ones

what the new feature added untul now in new revision since 0H0EAB (May 2008) ?
I ask my supplier, they give me the production code MHC-9000-0000GE, what 0000GE mean ?

AFAIK :
* Presumably the first two characters are the year - 0F means 2006, 0G is 2007, 0H is 2008, and so on.
The next two characters are the month - 0B is 02 or February, 0I is 09 or September, AB is 12 or December,
although more recently a 0K - "011" or November - has also been reported.
The last two numbers, or more recently single letter, appear to be the batch number from that month.

All, would you help me replay quick please.. because i want to buy it in next few days, n stock is limited only 2-4 unit ready

thanks all

 

[samgab]

Hi all n hi DarkMorford,
where i can see the production code version (revision), is that on the box or in the unit ?

is anyone can help me to post the picture here, to show me where side I can find n see the code version of MHC-9000, so i can make sure buy the recent ones

what the new feature added untul now in new revision since 0H0EAB (May 2008) ?
I ask my supplier, they give me the production code MHC-9000-0000GE, what 0000GE mean ?

AFAIK :
* Presumably the first two characters are the year - 0F means 2006, 0G is 2007, 0H is 2008, and so on.
The next two characters are the month - 0B is 02 or February, 0I is 09 or September, AB is 12 or December,
although more recently a 0K - "011" or November - has also been reported.
The last two numbers, or more recently single letter, appear to be the batch number from that month.

All, would you help me replay quick please.. because i want to buy it in next few days, n stock is limited only 2-4 unit ready

thanks all

Yes, your edit is correct.
Here is my date of manufacture code, it's on a sticker on the underneath of the unit:

First Pair:		Second Pair:
0G	2007		0A	January
0H	2008		0B	February
0I	2009		0C	March
0J	2010		0D	April
0K	2011		0E	May
0L	2012		0F	June
0M	2013		0G	July
			0H	August
			0I	September
			0J	October
			0K	November
			0L	December

So my one is 0K 0B A... This means it was from 2011, February, First batch in February.

A recent one might be 0L or 0M?
The main thing is really just the first 2, to indicate the year. Who cares which month or batch really, unless there is a faulty batch.
So if you're buying new, so long as it's 0L or 0M for the first 2 characters, that should be a recently produced item.
Unless they've changed their coding method?

PS, there are no new features, so to speak. It's just a code for Maha to know which batch a particular unit was produced in, like a date code. When it first came out in the mid 2000's there was initially a bug or two which were ironed out in subsequent models, but that was all done in about 2006/2007, IIRC, and there have been no upgrades or updates that I'm aware of.
"If it ain't broke..."

http://www.candlepowerforums.com/vb...r-Maha-C9000&p=3610722&viewfull=1#post3610722

http://www.candlepowerforums.com/vb...r-Maha-C9000&p=3859358&viewfull=1#post3859358

 

[NeoLoop]

Thank you bro samgab,
for pic n quick respon, so nice share :thumbsup:

 

[AlphaBetaOmega88]

Hi, i am new to the world of re-chargeable batteries. Not sure if this has been answered to before or if anyone has encountered this situation, please enlighten me if anyone has info to share. Thank you.

1) I am using Powerex 2700mAH AA batteries for my wireless microphones and i am using the Maha MH-C9000 chargers. As advised by the re-tailer, i had done a break-in to all my batteries first before using them. After the batteries had been drained from usage, i recharged the batteries using the CHARGE mode with Charge rate set to 500. When the charging is completed (DONE was displayed), i noticed that the mAH values for the batteries were not anywhere near to 2700mAH. I got various values between 1800mAH to 2250mAH. Does this mean that the batteries are not fully charged? I tried emailing MAHA but they have not replied back.

2) What is the lifespan of these re-chargeable batteries or rather how do i know when i should replace these batteries with new ones? Is there any guidelines? Based on my current usage, i am charging these batteries 3 times a week.

Thank you for your help.:thumbsup:

 

[N8N]

I am guessing that your devices are shutting off before the cells are fully discharged, therefore you're not getting the full 2700 mAh of use out of them.

run a discharge cycle on some cells, the C9000 will cut off at 0.9V and tell you what the capacity of your cells is, that'll let you know which ones are degrading.

 

[NeoLoop]

When charging AAA cell then power blink (interrupted) for awhile, MHC9000 will reset setting to default 1000 mAh.
Why MHC9000 do not change charging rate default for AAA to 0.5c (400 mA ~ assume AAA 800 mAh) because default 1000 mAh is more than 1c ?
MHC9000 manual pdf recommendation, do not charging rate more than 1c, it's contradiction.
I already read NC2500 manual pdf there is 2 default charging rate setting for AA & AAA cell.