C. Crane Question/Problem

[jayflash]

I've found that, occasionally, one of four cells was not fully inserted in the charger. There doesn't seem to be any way to insure all cells are receiving a charge or discharge, is there? One very minor advantage of a series charger is that you know the cells are properly installed.

Is it safe to use a larger power supply or a cigarette lighter adapter? The charging current decreases as more cells are added so I'm assuming the limiting factor might be the input power available? Is the power split to the four channels by one central device or circuit, which may become overloaded, or does the wall wart supply each channel individually?

 

[45/70]

I don't think it has anything to do with the power supply. I think it has to do with the spring pressure.

Back when I first got mine I did occasionally have this problem with AA cells, but not D cells (never tried it with C's). I can only attribute the difference, to the length of the cells and the spring pressure applied. I did find that, if after inserting each cell, I turned them with my finger until they felt "tight", the problem seemed to go away.

I might add that my C. Crane is used primarily as a D cell charger anymore, as shortly after I got it, it was replaced by dedicated AA/AAA chargers, for those cells.

Dave

 

[jayflash]

This is definitely a design parameter. If only one cell is inserted, it will charge at about a one amp rate while four cells only get ~250mA each. Still, there doesn't seem to be a way of insuring each cell is getting charged.

 

[jayflash]

Upon testing a bit more I discovered the discharge load is highest with only one cell and is cut in half with two cells and only 25% with four cells - just like the charging current is divided.

Is there a way to force the CCrane into discharge mode other than faking a weak cell by temporarily shunting one cell with a resistor and then adding the remainder of cells?

Thanks for any feedback.

 

[45/70]

jayflash, the C. Crane is a parallel charger made by Saitek. Yeah, I know, you can't charge NiCd or NiMH cells in parallel, but it, in fact, does.

There were many discussions about this charger back 4 or 5 years ago. It has an ingenious algorithm that seems to work very well. As I remember, it was uncertain whether there was actually any individual cell recognition. It would seem there would have to be, but maybe not.

I remember checking the charge current on mine, and finding 1800 mA for one cell, and yes, it works out to 900 mA, 600mA, and 450mA for 2,3, and 4 cells respectively, as it is a parallel charger configuration. The discharge as I remember (this was about 4 years ago), was 300mA for one, and then divided up accordingly for 2,3, and 4 cells.

It would seem to me that, rather than trying to modify your charger, it'd be better to just get another one. I've been meaning to get a Maha 808-M for years now, but the C. Crane works fine, albeit slow, and I really don't charge D cells much, so haven't gotten around to it.

Dave

 

[jayflash]

Thanks 45/70. Well, one useful aspect is a charge/discharge rate can be chosen by the number of cells inserted. Unfortunately, for highest rate only one cell can be used at a time.

I'm guessing the charger also senses the condition of the cell or state of charge to some degree because the charging current will vary between different cells and from beginning of charge and end charge.

 

[45/70]

Is there a way to force the CCrane into discharge mode other than faking a weak cell by temporarily shunting one cell with a resistor and then adding the remainder of cells?

Sorry jayflash, I missed this earlier. I'm not sure what you're asking. Yes, you can alternate between charge and discharge (IDS) using the "Discharge System Overide" button, if that's what you mean.

I dug up this link from an old computer. As I remember, this page is hard to get to on C. Cranes site, as the charger has been discontinued for a couple years. Anyway, among some other potentially useless information, there is a .pdf manual that you may find useful, if you don't have it already.

Dave

 

[jayflash]

Thanks for the help 45/70. My CCrane has a couple problems and one of them is that I can't force the charger into a discharge mode with the button. It's got some other issues too. Since I've already repaired it a couple times I think I'll just live with it as is and keep it for a backup.

Unfortunately, the new Titanium MD3000 charger only lasted a week before becoming unstable. Time to contact the dealer.

 

[45/70]

No problem, jayflash.

The only thing I can think of is, you have to press, and then hold down the button for 2-3 seconds before it'll take. You probably already know that though.

Yeah, like I said, I've had my C. Crane for 4-5 years and while I've been wanting to replace it, it just keeps plugging along. That's more than I can say for some chargers. One of my Maha C-9000's has had the display go wonky, so I'll have to send it back. :(

Dave