Airplane Batteries

Just an update: mechanic put the charger on the battery this a.m. He
said after an hour, it was bubbling all over the place. It is toast.
Looking for the comparable RG replacement right now. Oh well, learned a
lot, anyway. Thanks to all here for responding.

Aircraft batteries should be charged on a constant amperage
of about 2 amps and the voltage should be less than 14.5
volts. Standard automotive chargers will fry an aircraft
battery.


--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


wrote in message
...
| Just an update: mechanic put the charger on the battery
this a.m. He
| said after an hour, it was bubbling all over the place. It
is toast.
| Looking for the comparable RG replacement right now. Oh
well, learned a
| lot, anyway. Thanks to all here for responding.

"Big John" wrote in message ...

Blueskies

You can also get from your wife if she uses it for her steam iron
(like she should) )

Been doing that for years.

Big John
`````````````````````````````````````````````````` ```````


Actually, I keep my wife's bottle of distilled full from the de-humidifier... ;-)

Also use it for the iridite mix....

Jim Macklin wrote:
Aircraft batteries should be charged on a constant amperage
of about 2 amps and the voltage should be less than 14.5
volts. Standard automotive chargers will fry an aircraft
battery.



Why? How is a 6 cell lead-acid aircraft battery different from an
automobile battery, other than having less capacity obviously.


Matt

Because they are different. The automotive charger is high
amperage and the plates on the aircraft battery will be
distorted by the high current. A trickle charger on "high"
is about a maximum charge rate for an aircraft battery. But
you are free to use any charger you want.


--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


"Matt Whiting" wrote in message
...
| Jim Macklin wrote:
| Aircraft batteries should be charged on a constant
amperage
| of about 2 amps and the voltage should be less than 14.5
| volts. Standard automotive chargers will fry an
aircraft
| battery.
|
|
|
| Why? How is a 6 cell lead-acid aircraft battery different
from an
| automobile battery, other than having less capacity
obviously.
|
|
| Matt

"Jim Macklin" wrote in message
news:BnzBf.69434$QW2.59809@dukeread08...
Aircraft batteries should be charged on a constant amperage
of about 2 amps and the voltage should be less than 14.5
volts. Standard automotive chargers will fry an aircraft
battery.

An amperage selectable one should not. A popular charger configuration out
there, is something like 2 - 10 - 50 amp chargerm and that should only be
putting out about 14.4 volts.
--
Jim in NC

Jim Macklin wrote:

Because they are different. The automotive charger is high
amperage

It might be, depends on the charger. My automotive charger is a 50 amp
car starter and a 20 amp charger. The charger will vary as the battery
gets charged. As the battery gets topped off the current drops to an
amp or so.


and the plates on the aircraft battery will be
distorted by the high current.

Funny, considering after starting the plane the alternator gives the
battery about 30 amps and does the same thing my automotive battery
charger does in that it reduces the amps as the battery charges,
eventually getting down to an amp or two after flying more than an hour.

Jim Macklin wrote:
Because they are different. The automotive charger is high
amperage and the plates on the aircraft battery will be
distorted by the high current. A trickle charger on "high"
is about a maximum charge rate for an aircraft battery. But
you are free to use any charger you want.

My auto charger has a setting for 2A, 10A and 50A boost. Why won't the
2A auto charger work?

Matt

If it is regulated and really 2 Amps, it will, but most
cheapy auto chargers are not well regulated and will over
charge aircraft batteries.

If I recall, the maximum recommended charge rate is 10% of
the amp/hour rating, so a "dead" battery will take 10 hours
to charge.


--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


"Matt Whiting" wrote in message
...
| Jim Macklin wrote:
| Because they are different. The automotive charger is
high
| amperage and the plates on the aircraft battery will be
| distorted by the high current. A trickle charger on
"high"
| is about a maximum charge rate for an aircraft battery.
But
| you are free to use any charger you want.
|
| My auto charger has a setting for 2A, 10A and 50A boost.
Why won't the
| 2A auto charger work?
|
| Matt

Airplanes must have their own physics section.