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Meindert Sprang Meindert Sprang is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 140
Default Just wondering, Ni-cd charger used on Ni-mh

"Jack Erbes" wrote in message
...
So for routine purposes and otherwise healthy NiMH cells, what would you
use? As an aside, I finally figured out that C/10 means 1/10th of
capacity and that C/20 or C/30 is a much better idea.


I must corrent myself here. C/10 is fine for NiMH. Faster than C/10 will
overcharge them when not stopped.

I have a DuraCell quick charger that is identified as a "Class 2"
charger but does not tell me much more than that. Do you know what the
charge rate on a Class 2 charger is? Output is 1.6V @ 1800mA.


No idea but the specs suggest that it pumps 1800mA in the cells. The
efficiency of NiMH is 66% so when you have a 2500mAh cell, it needs
2500/0.66 = 3800mAh for a full charge. That equals 3800/1800 = 2.1 hrs with
your charger. So to see if your charger works, put the empty cells in, and
check after 2.1 hrs if the charger has shut off of does so within the next
15 minutes or so. If it doesn't, disconnect it yourself.

Meindert