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Default 20VDC into 14.5VDC charger - okay, or no?

Master Mechanic is TRUE VALUE HARDWARE.
Generally those chargers fail because of a shorted battery pack, but
can fail due to surges in the power line or other things.
Be careful, I had one of those batteries explode once. Not in the
charger, but in the drill. This is not just a story, the thing just
went bang, a chunk of plastic was embedded in my arm, and pieces of
the battery were all over my living room. I was only drilling a 1/8"
hole in a piece of angle iron (leg on my wood burner). I recently
read on the web about someone who had their cellphone start on fire
from the battery. Nicads are dangerous. I have not used a cordless
device since that happened. Skil sent me a new drill after I
threatened them with a lawsuit, but I sold it. I'll stick to tools
with cords. Thats what extension cords are for. Not to mention that
they dont suddenly run out of power mid job


On 3 Dec 2005 09:44:04 -0800, "Fritz"
wrote:

My charger for my cordless drill recently stopped working. My drill is
dead as a doornail, and I've got projects pending. It's an off-brand
(Master Mechanic), and I've had some difficulty locating the
manufacturer. Efforts to purchase a new charger have gone nowhere.

So...I was able to determine that the fault lies with the AC/DC
converter ("wall-wart"). It's rated at 200mA and 14.5VDC, but at the
moment it's putting out essentially 0VDC (verified with my
multitester). I went to Radio Shack and purchased a 15VDC 1A wall wart,
with the intent of cutting and splicing it to the charger, but when I
tested it's output myself, it's actually kicking out 20.33VDC. This
seems high.

What happens if I solder a 20.33VDC output to a charger that's used to
operating with 14.5VDC? Will it damage the battery? Cause an explosion?
Other deleterious effects?

Radio Shack also had a (rated) 12VDC wall-wart. If it runs hot like the
15VDC version does, I might actually get pretty close to 14.5VDC. Would
that be a better idea? Do the outputs from these low-grade AC/DC
converters always vary that much from their rated output? And does
anyone sell converters that will match the OEM one fairly closely?

ff