>It comes up again - the battery condition is "important" - if that is strong
>enough.
You bet it is . . .
>I have mentioned it before and would like to do so again.
>
>How do use simple fellows know that the battery is not up to it? Simply, the
>first most of us know is that the battery won't start the engine. By then I
>guess it's a bit late????
True. This is why the battery should be given the same
kind of attention in terms of preventative maintenance as
other things in the airplane. For example, we replace oil and
filters based on a schedule . . . not because the engine is at
risk of damage if the commodity is used a few hours longer
but because "it's time to renew it to INSURE ongoing airworthiness."
We replace tires not when they won't stay round any more but when
the tread wear falls below a certain point.
>Any plan to give "us" an article on battery care and covering vital signs as
>to health, and when it's at it's "use by" date? A discussion on voltmeters v
>ammeters might be helpful - I for one, as a layman, am confused by many
>learned comments.
It can be pretty simple. You have two choices:
(1) build and use the battery capacity tester described in an
article on my website at:
http://www.aeroelectric.com/articles/battest.pdf
or
(2) do periodic replacment of a battery based on time just like
you do oil and air filters. Assuming that you plan to use
the best kind of battery you can buy (recombinant gas) then
every two years for the average day/vfr airplane is probably
a good benchmark. For airplanes flown long cross-country at
night or IFR might want to look at yearly replacment. I've
suggested that some airplanes which benefit from dual battery
installations get a new battery in the main slot and move the
main battery to the aux slot yearly. For most folk this is
a 60-75 dollar expense that is trivial compared to other
operating costs of the airplane. If one objects to the
"easy" methodology, then see suggestion (1).
Variations on the theme arise when the battery has been
inadvertently discharged . . . and sets for a long period
of time (left the master switch on). Then a capacity test
is in order. If the battery seems to be getting weaker in
terms of cranking the engine, then a capacity test is in order.
An accurate voltmeter that indicates an operating bus voltage
no less than 13.8 and no greater than 14.6 will assure you
that the battery is being maintained by ship's alternator.
RG batteries do not need attention for long term (over
winter storage). Put away charged, they're good for a year
or more with no attention. Put away discharged and they're
recycle material when you come back.
Pay just a little more attention to battery selection and
condition as described above and the problem of sticking
contactors will be a long way down on your list of concerns.
Bob . . .
--------------------------------------------
( The only time you don't fail is the last )
( time you try something, and it works. )
( One fails forward toward success. )
( C.F. Kettering )
--------------------------------------------
http://www.aeroelectric.com
|