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How long do you charge 50mAh cell?
Posted: Fri Jul 18, 2003 3:14 am
by Matic
This 45 second charge is a joke, right ?. The charger on the transmitter charges the battery with 700 mA so fullcharge will take about 4 minutes. Yes that`s right you can charge your Bit 4-5 times for full charge.... not to mention 200 mAh cells
Posted: Fri Jul 18, 2003 8:23 am
by Namuna
I'm curious what transmitter you're using that puts out 700mA? I've put my Digital MutliMeter on a Bit charge-bay (connected to the transmitter), with AA alkalines I get a reading of over 2A.
Posted: Fri Jul 18, 2003 8:55 am
by Matic
I used Microsizers transmitter and a Duracell battery
Posted: Fri Jul 18, 2003 9:19 am
by hogjowlz
charge until the battery gets warm.
Posted: Fri Jul 18, 2003 6:20 pm
by ph2t
You can punch up to 1.6A for 2 minutes into the stock batts, more than that and you got WW3.
The best charge is 1/10 of the rating for 14 hours.
50maH batt would be 5mA for 14 hours.
200maH batt would be 20mA for 14 hours.
This charge cycle would get you he best runtimes period!
ph2t.
Posted: Fri Jul 18, 2003 6:40 pm
by CaboWabo
lol@ph2t "WW3"
Posted: Fri Jul 18, 2003 7:18 pm
by ph2t
Been
.
ph2t.
Posted: Fri Jul 18, 2003 7:23 pm
by ph2t
Namuna wrote:I'm curious what transmitter you're using that puts out 700mA? I've put my Digital MutliMeter on a Bit charge-bay (connected to the transmitter), with AA alkalines I get a reading of over 2A.
Hey Hulkster, was this reading taken in-line with the car whilst it was charging? Or did you put the +ve and -ve probes directly across the charge terminals? If it's the later then the reading would be incorrect since you need to measure current in-line with the load in question.
Keep in mind that a multimeter has a resistance close to zero when it's in current reading mode, that's why you'd have such a high current reading. You were effectively shorting the charge terminals, again assuming you did the former mentioned above, otherwise I want that controller, lol!
Coolies,
ph2t.
Re: How long do you charge 50mAh cell?
Posted: Fri Jul 18, 2003 7:26 pm
by ph2t
Matic wrote:This 45 second charge is a joke, right ?. The charger on the transmitter charges the battery with 700 mA so fullcharge will take about 4 minutes. Yes that`s right you can charge your Bit 4-5 times for full charge.... not to mention 200 mAh cells
Theoretically yes, but in reality a lot of this energy is lost as heat. The NiCd/NiMh cells breakdown under high charge currents. Eg: I found not much difference in runtimes charging at 50secs at 1.2 or 1.6A. See my custom charger thread in wiered science for more info.
ph2t.
Posted: Sat Jul 19, 2003 9:05 am
by crazydave
Watching voltage for peak, the stock NiCd batteries consistanty peak at about 3.5 minutes. I think the stock batteries are taking more than 50mah. I'm estimating more like 70 or 80mah, though I'm not sure how I came to the this conclusion than maybe because 150mah batteries consistantly peak at around 6-7 minutes.
Anyone know how to read milliamp hours (mah)? I assume you measure the current put out over a period of time, but then there's got be some math after that, and that's my weak point.