Maha MH-C9000 SUPPORT / FAQ - continuation

[PEU]

And it arrived! They followed my request to declare the item as: Warranty replacement of no commercial value and I ended paying ZERO at customs!

Great service, kudos to Maha!


Pablo

And Im going to receive a new one...

The replacement I received didn't work correctly, it left batteries with around 380ma (eneloops AA) compared it with the original one that had the rightmost bay damaged the batteries charged to 2000ish ma

Maha support asked me to do a couple of tests, send them photos of the results (I sent videos) and they determined there was indeed a problem with the charger.

Now Im curious, when I receive the new unit I will check/compare the multitude of test points the pcb board has.
If anyone went this route and have some insight, I would like to know.


Pablo

 

[TorchBoy]

If anyone went this route and have some insight, I would like to know.

Not quite what you mean, but I've been the route of having several go faulty (which I don't at all think is typical). Maha's customer service has been great, though.

I don't know anything about test points but it sounds interesting.

 

[PEU]

Received the new one, asked them to send 4 batteries to test the new charger and they did that too (4x powerex 2700)
Now Im doing a break in cycle to all of them, hopefully when I return to the office on monday they are charged correctly.


Pablo

 

[TorchBoy]

asked them to send 4 batteries to test the new charger and they did that too (4x powerex 2700)

Did you pay for those or did they?

 

[PEU]

Did you pay for those or did they?

No, they send them for free after I asked to send the batteries they used to pretest the charger before sending it, but the battery package was closed, so I guess they just tossed a similar package of the batteries they used, I really appreciate that.
I really hope this new charger works as expected. Will post the result tomorrow when I return to the office


Pablo

 

[TorchBoy]

That's very nice of them. I note that it's almost 2 years and 11 months since I bought mine. My last MH-C9000 has been going quite well, so I hope I won't need the 3 year warranty again.

 

[PEU]

The batteries charged to almost all their capacity (real 2540 vs 2700ma branded) but we all know there is always a 10% "error" in the marketing packages...

Well, I also hope I don't need the warranty again, Im really gratefull for the excelent maha customer service.


Pablo

 

[tundraotto]

Its the customer service posts like yours, along with the opinions & info from the battery gurus (you all know who you are). It made my choice easy and boy am I a happy camper!! doing 3 refresh/anyze cycles and 1 break-in...and I am wondering who do people complain about this user interface??!?!? I mean come on - maybe MAHA can make one with a keyboard and charge $200 for that and pass the savings to us penny pinchers who realize the good price point this product is offered!!!

Awesome - I am happier with this than with my Ultrafire A10 that kicks butt @$17 - I mean really a TK11 R2 next to this noes not put the a10 to shame in the least - its pretty ghastly owning both of them and knowing what the price/size difference is....I am just glad I have both!!!!

See - even a blind squirrel finds a nut every now and then:thumbsup:

 

[jozek]

I've recenty bought MH-C9000 charger, as my brother have the same for some time and was very happy with it. I was using it for charging AA cells and all was working fine. Problems started when i try to charge AAA cells. With those batteries there is a contact problem on positive electrode. AAA batteries are very loose, and it often stop charging sometimes. Also smetimes there are small "sparks" and buzzing becouse of that.
I went to see my brothers charger and it turned out the shape of electrodes on his charger are different wich makes AAA batteris "click" in correct place nicely (see pictures). On mine with some force i can push batteries so they would click in those two small bottom "peaks" but then it badly scratches electrodes on the cell.
Does any1 have any problem as me, is this new type of charger or smth?
Mine is "0101A" my brothers "0H0DA".

My brother electrodes:
http://img237.imageshack.us/i/old2.jpg/ (fixed)

Mine:
http://img46.imageshack.us/i/new2a.jpg/

Scratches on batteries:
http://img269.imageshack.us/i/98957996.jpg/
http://img203.imageshack.us/i/31988544.jpg/

 

[Turbo DV8]

Pictures of your brother's electrodes aren't coming through. I had a similar contact problem with AAA cells on my two C9000's, but it was the negative end. I returned both chargers.

 

[Mr Happy]

:welcome:

The C9000 can have a problem with AAA cells, but it is usually found to be at the negative end rather than the positive end. When you insert the batteries, do you push the negative end down firmly first, and then while holding it down click the positive end down into position? That is the only way I can securely insert AAA cells into my C9000.

Also, I have to make sure the wrapper does not wrap around the negative end of the cell. If it does I have to trim it off with scissors to expose plenty of metal. Otherwise the plastic gets in the way of the spring and prevents good contact.

 

[jozek]

Fixed link on previous post.
Contact on negative end is fine with batteries, end yes i place negative end first then push batteries down. The thing is that if i turn charger upside down and shake a bit then batteries will fall of from charger, there is not eneough pressure to keep them. As i mention i could push them them further down, so they would catch on those two bumps, but it scratches batteries badly.

As for minus electrodes there some differences on them aswell.
The old ones pics: http://img251.imageshack.us/i/oldminus.jpg/
and those r mine : http://img192.imageshack.us/i/newminus.jpg/
IMO the new ones have better connection there.

When i plug batteries on mine it seems like the plus electrode in charger is too deep, and battery case stops on plastic cover of charger. Its worst on 1 and last sockests, and the issue is smaller on the middle ones.
http://img163.imageshack.us/i/newbattery.jpg/

On the old chargers everything works great, and connection sie nice.
http://img230.imageshack.us/i/oldbattery.jpg/

If i push batteries very hard (alot of force needed) then connection is nice, but it scratches battery and its difficult to remove them after (again a lot of force is needed).
http://img163.imageshack.us/i/newpushed.jpg/

Yesterday when i was charging one of batteries it switched to default charging mode (1A) for a 800mAh eneloop . Most likely there was no proper connection and the charger stoped charging, then after some time connectioion got enough for charger to recognize putting battery in slot so it started chargin it.

Hope that explains some things, and sorry for bad photo quality as i only have a camera on my mobile phone.

 

[clintb]

For those having problems with AAA's springing back out, I've found an insertion method that has not failed me yet on both of my C9000's.

Insert the negative end first, and push back on it slightly when inserting the positive end. Once snapped in, give the cell a gentle roll from side to side, as if you're spinning it along the lengthwise axis. Doing so will make the negative contact move more towards the center of the cell's negative end.

 

[Bones]

The method described by clintb works for me as well jozek.

The trick is to keep to keep the negative tang compressed while slipping the positive end of the cell into place. The positive post of the AAA cell also has to slip past the protrudence in the center of the positive tang. It helps keep the cell in place.

For what it's worth, the negative tangs will become easier to compress after they've been used for a while. In fact, you can help this along by deliberately compressing them a few times with a rod that's small enough to fit through their openings. A wooden stick whittled to shape will work quite well. It also won't scratch or otherwise damage the tang or the charger providing you don't get carried with the amount of force used.

Please note that the positive tangs are locked into place, so don't attempt to compress them.

More on loading the MH-C9000:

http://www.candlepowerforums.com ... post2810241
.

 

[TorchBoy]

Insert the negative end first, and push back on it slightly when inserting the positive end. Once snapped in, give the cell a gentle roll from side to side, as if you're spinning it along the lengthwise axis. Doing so will make the negative contact move more towards the center of the cell's negative end.

I do that also, to make sure it isn't going to pop out again (which I very occasionally get).

 

[45/70]

I think it may be important to note, that the newer C9000's (0I0IA, at least) have a substantially different negative contact for AAA cells than the older models. It really shouldn't work that differently, but does seem to.

At first glance the new ones appear like a flat screwdriver blade, as opposed to the angled bent strip like the old ones have. Actually the new ones are also a bent strip, but are bent more into a 180 degree loop sticking straight out, rather than at an angle. I hope that description makes some sense. A picture isn't possible for me right now.

The newer version seems to be more "picky" about AAA insertion. I find that just inserting them like clintb described works well, but leave out the twisting motion. If I just snap them in and leave it at that, it seems to work better. When I twist the cells (as I am in the habit of doing), they seem to loose contact.

I do that also, to make sure it isn't going to pop out again (which I very occasionally get).

This doesn't seem to be a problem with the newer version. I imagine that is why the contact is more straight on, rather than angled. There is no tendency for the cells to pop out.

Dave

 

[Mr Happy]

For some reason the contacts for AAA cells seem to be the weak point about the C9000. I have no idea why Maha seems to struggle with this.

For what it's worth, the old negative contact style would have been fine if only the height of the spring had been raised a bit, so that it contacted with the middle of the cell instead of the bottom.

Totally changing the shape of the metal spring as has apparently been done with the newer models does not really address the original problem.

It seems like Maha know what they are doing with electronics, but totally fail when it comes to mechanicals.

 

[Bones]

There may actually be three iterations of the negative tang for the AAA cell 45/70.

The first, with a decided down angle to the horizontal portion of the tang. A second, with less of a down angle. And, finally, a third with less of a down angle, but also with the same protrudence that has always been formed into the negative tang for the AA cell.

These images might help illustrate what we're saying, the latter two were provided by jazek in post 1:


-

-
-

If you're really having problems keeping AAA cells seated, and you're willing to open up your MH-C9000, it is possible to raise the negative tang in it slot by decreasing the down angle of the horizontal portion of the tang.

If nothing else, perhaps Maha will finally see fit to simply extend the length of the upright portion of the tang a few millimeters. It's hard to believe they actually thought to modify the tang by adding the small protrudence that's always been formed into the AA tang without thinking to raise it a bit as well.

 

[jozek]

Thanks for all feedback about this problem, but everyone concentrates on negative end contact problem, but its not the case here. Negative end contakt is fine and very steady, its the positive end that gives problem.

Compare the shape of positive tans on those two pictures (no big hill in the middle ). On mine there is nothing to hold call in place and it have a tendency to slide on tang upwards and loosing contact there. This is not a prolem with negative end. Rotating pushing batteries up a bit, nothing makes 100% sure that you wont loose contact. Even stomping on the floor with foot can make it stop charging :/

-

 

[TorchBoy]

Compare the shape of positive tans on those two pictures (no big hill in the middle ). On mine there is nothing to hold call in place and it have a tendency to slide on tang upwards and loosing contact there.

Could it be that a machining step was somehow missed?