Rob Erdos
Well Known Member
Hi Guys!
My wife and I were on the last leg home from a wonderful long weekend away in our RV-6. I got some strange electrical indications, and have no idea what I was seeing. If anyone has ideas I would be very appreciative for their insights.
Aircraft Configuration. Our IFR RV-6's electrical system consists of a Plane-Power AL12-E160/B 60A internally regulated alternator and a standby B&C SD-8 alternator. They are wired through a three-position toggle switch as follows: ALT-OFF-STBY. I have an Odyssey PC-680 battery on the firewall. The panel is dual Dynon Skyview, which displays main bus volts and amps.
The electrical schematic is as follows:
[http://i1106.photobucket.com/albums/h373/RVRob/Electrical Schematic_CF-SPB_zpsifkg0aje.gif]
Indication. Operating on the primary alternator, the voltage is normally steady at 14.1 V. The ship normally draws about 15A. Over the last few flights I momentarily thought I saw voltages around 12V, but the voltage recovered just as soon as I noticed it.
On the last flight, the voltage dropped to 12.2 V, then periodically began to fluctuate from 14.1V down to 12+/-0.5V. The current draw seemed steady. I thought, "Rats! My voltage regulator is failing!" I shed some load to about 7A and switched to the standby alternator, but the voltage fluctuations persisted.
I tried turning off everything that I safely could live without. No change.
Upon landing, I selected both alternators off. The battery voltage was 15.1V! When I selected either the Primary or Standby alternator, the voltage dropped to around 14.1V, then began to fluctuate again.
I'm thinking that it might be an internal failure of a cell within the battery.
Has anyone seen anything like this? Ideas greatly appreciated.
My wife and I were on the last leg home from a wonderful long weekend away in our RV-6. I got some strange electrical indications, and have no idea what I was seeing. If anyone has ideas I would be very appreciative for their insights.
Aircraft Configuration. Our IFR RV-6's electrical system consists of a Plane-Power AL12-E160/B 60A internally regulated alternator and a standby B&C SD-8 alternator. They are wired through a three-position toggle switch as follows: ALT-OFF-STBY. I have an Odyssey PC-680 battery on the firewall. The panel is dual Dynon Skyview, which displays main bus volts and amps.
The electrical schematic is as follows:
[http://i1106.photobucket.com/albums/h373/RVRob/Electrical Schematic_CF-SPB_zpsifkg0aje.gif]
Indication. Operating on the primary alternator, the voltage is normally steady at 14.1 V. The ship normally draws about 15A. Over the last few flights I momentarily thought I saw voltages around 12V, but the voltage recovered just as soon as I noticed it.
On the last flight, the voltage dropped to 12.2 V, then periodically began to fluctuate from 14.1V down to 12+/-0.5V. The current draw seemed steady. I thought, "Rats! My voltage regulator is failing!" I shed some load to about 7A and switched to the standby alternator, but the voltage fluctuations persisted.
I tried turning off everything that I safely could live without. No change.
Upon landing, I selected both alternators off. The battery voltage was 15.1V! When I selected either the Primary or Standby alternator, the voltage dropped to around 14.1V, then began to fluctuate again.
I'm thinking that it might be an internal failure of a cell within the battery.
Has anyone seen anything like this? Ideas greatly appreciated.
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