Alternator?

[Ghery]

I was up with the CFII this evening shooting the ILS into OLM (beautiful VFR evening) and the panel lights dimmed and the ammeter started showing a slight discharge. Dumping loads (radio, DME, landing and taxi lights) resulted in the panel lights coming back up (step function). Also some extra whine in the intercom audio when the lights dimmed. We called it an evening, told the tower we had an electrical problem and would be landing.

Sound like an alternator or voltage regulator? Called it in to our maintenance officer, so it's his problem, but has anyone experienced this? C-182P. Nice thing about a club, call it in and it will get fixed. I guess we'll fly the Arrow tomorrow evening.

 

[gismo]

I was up with the CFII this evening shooting the ILS into OLM (beautiful VFR evening) and the panel lights dimmed and the ammeter started showing a slight discharge. Dumping loads (radio, DME, landing and taxi lights) resulted in the panel lights coming back up (step function). Also some extra whine in the intercom audio when the lights dimmed. We called it an evening, told the tower we had an electrical problem and would be landing.

Sound like an alternator or voltage regulator? Called it in to our maintenance officer, so it's his problem, but has anyone experienced this? C-182P. Nice thing about a club, call it in and it will get fixed. I guess we'll fly the Arrow tomorrow evening.

If you heard an atypical whine, I'd say you lost a diode in the alternator. When that happens the ripple voltage (AC on top of the DC) increases dramatically and the output drops to a fraction of the normal output.

 

[Ghery]

My suspicion, as well. Talking with the maintenance officer for the plane he has also seen the alternator belt slip in cold weather. Plane's going off-line in a day for annual inspection, anyway, so they can add this to the list of things to look at.