Ask Mr. Fixit
March 10, 2006
Camcorder Disorder
by Bud Jillett
Dear Mr. Fixit,
My
husband and I have a JVC Compact VHS-C Camcorder that we recently tried to use
after not using it in almost a year. We have three (3) batteries for it, which
we charged overnight. However, none the batteries acted right in the charger,
according to the instructions. Two batteries are the same: they are JVC
BN-V11U. The other battery is a bit thicker but otherwise the same dimensions
and fits in our camera just fine. It is: CB-2NiMH.
The
first two batteries acted normal in the charger at first. The charger light
blinked for quite awhile but then went out completely. The instructions say the
charger light should glow steady once the battery is done charging (as opposed
to going out).
We then
put the bigger battery in the charger figuring it would take longer and we went
to bed. By morning the charge light was still blinking and the battery was hot,
hot, hot! Needless to say we unplugged the charger.
Odd
thing is that the only battery that worked after all that was the one that
never finished charging and got so hot. We are afraid to use that battery,
though, much less attempt to charge it again.
The
camera works fine when plugged directly into the adapter, which is also used to
charge the batteries. This makes us think the charger is fine, be now we’re not
sure of anything.
Can you
help?
Sincerely,
Camcorder
Disorder on the Eliot Border
Dear
Disorder,
Stories
like this make my heart skip a beat. You were wise to turn off the charger when
the battery got hot. I am thankful that’s all that happened—especially since
you and your husband were (presumably) sleeping!
The big
battery – throw it out! It’s most definitely the wrong battery for your charger.
It will work in your camera because it’s a 6V battery that has the same
configuration as the battery your camera uses. If you had the right charger, it
would even be a great battery for your camera.
The big
battery is a Nickel Metal Hydride (NiMH) battery that has longer life than the
Nickel Cadmium (NiCad) batteries that came with your camera. However the charge
process for a NiMH battery is different than for NiCad batteries. NiCad battery
chargers detect maximum charge by monitoring the battery’s voltage and
automatically shutting the charger off when the monitoring circuit detects a
noticeable dip in peak voltage.
NiMH
batteries do not have this characteristic when they are charging. Therefore, a
NiMH battery in a NiCad charger will continue charging even after in
reaches peak voltage!
This causes the excess energy to be converted to heat, which heats up the
electrolyte in the battery as well as the battery casing. This is a very
dangerous situation that can cause a small explosion, a meltdown, or even a
fire under the right circumstances. At the very least it damages the battery.
Thus a battery designed for longer life suddenly becomes useless after a few
“charges.”
By this
point (after your heart settles), you’re probably wondering why, then, did the
NiCad batteries fail to charge if they are the right ones?
The simple
answer here is that the batteries are old. On top of that, they had lain
dormant for a year, which caused them to “go flat.” NiCad batteries that have
gone flat can no longer take a charge.
The simple
solution? Replace the batteries with the exact same part number (in your case
JVC BN-V11U). Notice to you and all readers: never replace rechargeable
batteries with anything other than the original part number. If you must use a
third-party replacement, make sure the manufacturer recommends this replacement
for your gadget and its charger. Just because a battery will work in
your device, it does not mean your charger is appropriate for it.
—Mr. Fixit
Please send
your Mr. Fixit questions via U.S. Mail to:
The Weekly Sentinel
P. O. Box 308
North Berwick, ME 03906
Or submit
them via e-mail to: bud@jillett.com.
.
