13.6V alt output?

[Ironflight]

I don't have enough time in my day to read the aerolectric list...

I think I shall simply retire from the field of battle, and go flying.....

Paul

[sprucemoose]

Me too. It's made it into the 20s today, positively balmy around here.

You call this a battle? You really should spend some time on Aeroelectric list! Although from your reply, you obviously have!

[gmcjetpilot]

What alternator do you have. If it has a remote voltage sense and it comes disconnected it will go the 13.6 volts. I am guessing because I have no idea what alternator you have, George

Check your wiring and make sure the IGN lead and S lead (if you have an S lead) is connected to a buss or battery source. It could be the regulatro, brushes, a who lot of things.

If you have a L connection I might suggest you use it. When you have "soft faults" where the alternator has an issue (like the remote sense lead becomes open or disconnected from a power source) the light will come on. The light is a great Hi/Lo volt light.

Many people just tie the IGN and "S" wire together to simplify wiring (not all ND alternators have a S wire). I personally think you would use the remote sense as designed, which is to the battery.

here is the trouble shooting tree for a Toyota but may apply\
http://www.autoshop101.com/forms/h8.pdf


Here is a wire diagram I made up (correction 5 amp to IGN wire may be 1 amp since the regulator only needs a small current unlike an external regulator.)
http://img519.imageshack.us/my.php?i...rwiring2fh.jpg

George

[kevinh]

Thanks all for the good advice (particularly that great Toyota document). I was able to start my investigation today, but got called away to the office.

I'll post a result once I can get back to the airplane - probably not till Tuesday.

[dmeloche]

I'm a glutton for punishment so i'll chime in,

I have the internally regulated alternator from vans and the odessey battery. My EIS consistently shows only 13.5v. I've been flying the plane since July. I was at first a little concerned about it but have had no problem starting the aircraft or any low voltage situations. I have a rather low demand electrical system though and haven't done much night flying but I do use the landing/taxi lights a lot near the airport for visualization purposes and have the strobes on constantly. I'm not sure if i would get to concerned about this unless i was planning to do long distance night IFR flying.

Doug Meloche

[gmcjetpilot]

Originally Posted by dmeloche

I'm a glutton for punishment so i'll chime in,

I have the internally regulated alternator from vans and the odyssey battery. My EIS consistently shows only 13.5v. Doug Meloche

To deep charge a SLA/AGM battery it needs 14.2 volts min. (14.5 best) After full charge, 13.6 is good for trickle charge, but will not bring the battery up to full capacity if drained. 13.5 volts is too low, just my opinion, no arguing, if it works it works for you cool. George.

[Ironflight]

Eureka! If it hadn't been for this thread getting me to thinking (and a three-hour ride on Southwest this evening to give me the time...), I wouldn't have fiugred out what happened to me on my First Flight Day! this is the answer - and it proves that the Oddyessy wants more voltage for charging!

I used a nice workshop 40 Amp 12 volt power supply as ground power for the -8 throughout it's construction. I moved that out to the airport for final testing during assembly, and it still is connected to my ground power plug, and gets used in the hangar on occasion. For most of the construction, the ship's battery was not connected, and I only installed it when we started doing engine runs.

On the day of the first flight, I got out and powered things up about an hour early, using the external power supply (ironically, to "Save" the battery). When it came time to start and go fly, without the ground power connected, the engine wouldn't crank - the battery was low! (Long story short, we jump started from the truck, and had a good flight)

Now I realize that what is happening is that my power supply only puts out about 13.5 volts. That's fine for running things during test and checkout. But when the battery is in the system, even with the ground power enabled, I'm running off the battery - and the power supply is too low to bring it back up.

Good lesson, and good information from this thread!

Paul

[kevinh]

Just an update:

Last night I finally had some time away from work to test and prod things. I tried the various good suggestions, but the fix (at least in my case) was to replace the alternator. All is well now - back at 14.2V.

When I originally installed the alternator I suspected that someone might have done the sleazy 'return something broken and claim unneeded' thing - it was a bit more bunged up than I expected a rebuilt alternator.

The replacement I just installed was new and shiny - perhaps my original alternator was not actually rebuilt but merely reboxed.

Kevin