Battery charger questions

[Eugene Varnavsky]

I've got a "Fast" Uniross charger and two AA-sized Uniross Ni-MH 2000 mAh
accumulators.
This charger, as documented, gives 250 mAh for AA batteries for 5 hours, and
then turns to trickle mode.
I measured the current, and it's only 150, not 250!

Anyway, this charger seems to be inappropriate for 2000 mAh accums, because
250 for 5 hours means 1250, instead of required 2000.
Can i use it to charge 2000 mAh accums? Will it damage them if they will be
used not completely charged?
Is there a way to tweak this charger for higher current or longer time?
And, at last, why it gives 150 mAh, not 250 as documented?

P.S.
Charged accums give 1.38 volts, and trickle mode is 15 mAh.

 

[Robert Baer]

I've got a "Fast" Uniross charger and two AA-sized Uniross Ni-MH 2000 mAh
accumulators.
This charger, as documented, gives 250 mAh for AA batteries for 5 hours, and
then turns to trickle mode.
I measured the current, and it's only 150, not 250!

Anyway, this charger seems to be inappropriate for 2000 mAh accums, because
250 for 5 hours means 1250, instead of required 2000.
Can i use it to charge 2000 mAh accums? Will it damage them if they will be
used not completely charged?
Is there a way to tweak this charger for higher current or longer time?
And, at last, why it gives 150 mAh, not 250 as documented?

P.S.
Charged accums give 1.38 volts, and trickle mode is 15 mAh.

Since the charger "switches" over to trickle, no damage can occur; the
rating of thebattery is not relevant.
Likewise, just leave the batteries in longer.....

 

[Harry Bloomfield]

| Anyway, this charger seems to be inappropriate for 2000 mAh accums, because
| 250 for 5 hours means 1250, instead of required 2000.
| Can i use it to charge 2000 mAh accums? Will it damage them if they will be
| used not completely charged?
| Is there a way to tweak this charger for higher current or longer time?
| And, at last, why it gives 150 mAh, not 250 as documented?
|
|

I have one as well and I measured it to be delivering 180mA and I was
not very satisfied with it. They work on a timer from the time the unit
is plugged in, which is set for the aH of batteries it is supplied
with. One way to defeat it, is to unplug it after 2 hours, then plug it
straight back in for the 5 hours, giving 7 hours total charge.

As indicated, I was not very satisfied with it, so I went out and
bought a DeltaV charger for AA/AAA's. I can plug any mH capacity cell
into this, in any state of discharge, and it charges it up to a
properly measured state of full charge. I'm delighted with this charger
and I seem to be getting longer use out of the cells between charges.

I have relegated the UniRoss to secondary use, where upon after
charging with the (only fully used cells), I then top the charge off
with the DeltaV charger.

As a means of keeping cells topped up with a dumb trickle chargers, I
use a 24 hour time clock set to come on for one hour per day. Into this
I have a 6 way mains outlet, which allows me to plug six of these types
of charger in at the same time. I keep a battery drill, battery
soldering iron and a small PCB drill ready for instant use by this
means, without damaging the cells due to a constant trickle charge
flowing through them.

--
Regards,
Harry (M1BYT)...

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