>
>Here is what happened:
>
>When I built the plane, I installed a level switch in each tank to
>indicate that it was down to 5 gallons. A warning light illuminates on
>my alarm panel indicating which tank is low. As it turned out, the bulb
>indicating low fuel in the left tank was shorted, and the breaker tripped
>when I made steep left turns (I guess the turns weren't coordinated, or
>this theoretically wouldn't have happened).
>
>Interesting huh?
>
>I learned several things from this experience:
>1) Resetting a breaker in flight is not necessarily a bad thing.
But did you KNOW that before you were on the ground
and able to make a considered diagnosis? Knowing
what you know now, would you take a similar situation
in the future and choose to shift from pilot-mode
to mechanic-mode in an effort to see if an inflight
reset is a good idea?
>2) A breaker helped me diagnose this problem.
. . . and a popped fuse would not?
>3) I never say a circuit will never fail.
. . . which is why we have fuses and circuit breakers
in the first place.
>In this unusual case, being able to tell when the short occurred
>(watching the breaker pop) helped me solve the mystery. Had this circuit
>been protected with fuses, I don't know how I would have ever solved the
>mystery.
Why not? When chasing an intermittant short, how about
rigging a light bulb in series with the bus to feed
the affected circuit . . . you can wiggle and fiddle
while watching the light . . . when the light is illuminated
brightly, the short is in effect. When you're diagnosing
the same kind of problem with a breaker, you can clip a
lightbulb across the open breaker for the same diagnostic
tool. This is NOT an unsual case at all . . . MANY
faults present themselves initially with an intermittant
condition . . . which is one of the reasons I don't
think Polyfuses are such a good idea . . you might
fly around with an impeding failure when it first
manifests only an intermittant condition and not
know it until it craps for good.
>However, in spite of this experience, if I were to do it over
>again, I would keep it simple and install only fuses.
Bob . . .
////
(o o)
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