garrys@tampabay.rr.com wrote:
> The voltmeter in my panel reads 11.9 volts with radio, GPS and transponder
> turned
on, and reads 12.1 volts when I turn off the radio, GPS, and transponder.
My Ammeter reads 003.............whatever that means. Increasing my RPM from
4900 to 5200 increases the voltmeter reading by about .1 volt. Do I have a
voltage problem?
Before condemning the RC Allen, what's going on with your charging system and/or
instrumentation? A fully charged battery in good condition will not draw 3A
---From the alternator at 12.3 V. Even in not quite new condition, it should
draw
nothing. Depending upon the battery construction and chemistry, 13.8V is a
typical float charge. However, the way airplanes are used, 14.0 or even 14.2V
is tolerable. The first thing I would check is the battery voltage at cruise
RPM after the alternator has had a chance to replenish starting juice, with a
digital multimeter of presumed accuracy. If you don't want to spring for a
Fluke
or a Keithley, I have found that either Crafstman or Radio Shack can be accurate
enough.
My RC Allen unflags at 12.3V, and on the way down, flags at 11-something. So I
presume the low voltage if what you report is accurate is adequate volts, at
least not to cause it to tumble. This is an FAA-approved instrument, common in
big complex airplanes. One could easily have only low twelves on volts at
night,
on an ILS approach in the soup. We wouldn't want it to tumble, would we
now? [Shocked]
Also, does it tumble on the ground or just in flight? In any event, after
you've
sorted out any voltage prob, and need advice on the gyro, post back. I have
a tax client who has run an instrument repair shop since only around 1970. She
answers relevant questions candidly.
Fred F.
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