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mborodave
05-25-2011, 12:31 PM
Hello, Been flying my mSR & 120SR for a coulpe of months now. The chargers for them are fine. I recently got my 20 yr old rc-10 car up and running that uses 6s 7.2v nicad packs. I bought 3 nimh packs and they are working great. The charger I have for it is also 20 yrs old. Ultimately I'm wanting to get into larger helis that require larger packs similar to the one for the rc-10.

When I am looking at new chargers to handle these 6s packs, is it suitable to use a battery charger for a car. The one I have is 12v and varies in amps up to 50 (pushing up to 600 watts). These chargers are fairly inexpensive compared to some of the others I've seen (around $40 or less).

Any reason these power supplies are seemingly overlooked??

Thanks,
- Dave

desertstalker
05-25-2011, 10:40 PM
Any reason these power supplies are seemingly overlooked??

Are they Lithium chargers? RC helis all use some sort of lithium chemistry cells where some RC cars are still using NiCd/Nimh packs. The Ni based cells are too heavy to be good for aircraft.

The reason Li chargers are more expensive is the extra complexity and precision required when charging Li cells.

N4HHA
05-26-2011, 12:57 AM
Or are you asking if one of the 12V auto chargers will power a LiPo charger? Short answer, no.

mborodave
05-26-2011, 04:32 PM
I'm only looking to use a car battery charger as a power supply for a rc-grade charger for lipo's / nimh / nicd / etc..

Still would go though a icharger, or some equivalent, but would like to use a car charger as a power supply...

Is this a realistic expectation?

N4HHA
05-27-2011, 08:37 AM
Most newer automotive chargers will not output any voltage until a battery is connected. They then perform a brief test on the battery for state of charge and turn off the output several times when changing "stages". The older (or cheaper low current) chargers can output very nasty unregulated and unfiltered crap that almost doesn't pass for DC.

Phreak Out
05-29-2011, 10:45 AM
The older (or cheaper low current) chargers can output very nasty unregulated and unfiltered crap that almost doesn't pass for DC.

This might seem expensive, but you'll get ~12.5V of "clean" DC --> LINK (http://www.ronlund.com/mm5/merchant.mvc?Screen=PROD&Store_Code=RHPS&Product_Code=CDMPS&Category_Code=ELECCA)

Eventually, if the need to upgrade (example: charge two six-cell packs simultaneously) and you'll have a higher quality charger that can be useful like this, then you simply add another power supply, run it in series and you'll have yourself 25V @ ~47 amps (PHOTO (http://www.helifreak.com/picture.php?albumid=7109&pictureid=56303)).