R Alternator Fail

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baldesk
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R Alternator Fail

Post by baldesk »

Have any DA42-VI owners experienced a R Alternator Fail message shortly after startup at low RPMs? This is a regular occurrence in my new -VI. It seems to resolve itself, and not reoccur during the current cycle, if I increase power to the right engine shortly after startup. If I don’t increase power the error message remains and the Amps gauge dances around until I increase power slightly at which point the error message clears and the Amps gauge settles down. To be fair, I have not waited more than 10 seconds for the issue to resolve itself before adding power, mostly out of habit from similar experiences in my previous DA 40. Thoughts? Thanks.
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Re: R Alternator Fail

Post by CFIDave »

On my DA42-VI I had a similar behavior: When the engines were cold, right after startup (at idle RPMs) I'd get a R Alternator Fail annunciation that would appear momentarily until indications on the Amps gauge settled down. I suspect that is what you're seeing.

On my DA62 I get a similar indication while taxiing using differential thrust to turn the plane. Every time I bring the right throttle back to idle I hear a chime and see a R Alternator Fail annunciation on the PFD. I've seen this on some other DA62s I've delivered.

All of this is related to the automated alternator load balancing function that operates in a master-slave relationship. The left voltage regulator is the master that controls the right alternator as a slave. We've tried to diagnose this by swapping left and right voltage regulators, but the behavior remains the same.
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baldesk
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Re: R Alternator Fail

Post by baldesk »

Thanks for the info Dave. Very helpful as usual :)
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neema
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Re: R Alternator Fail

Post by neema »

We've had this behavior for a couple years now on our 42-VI. Only happens following a cold start at idle power.
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dgger
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Re: R Alternator Fail

Post by dgger »

neema wrote:We've had this behavior for a couple years now on our 42-VI. Only happens following a cold start at idle power.
For what it’s worth I see that exact behaviour on my NG as well.
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Re: R Alternator Fail

Post by ultraturtle »

neema wrote:We've had this behavior for a couple years now on our 42-VI. Only happens following a cold start at idle power.
Me too.
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Re: R Alternator Fail

Post by Tilemachos »

Yes I confirm the same on NG & VI
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