Testing alternators at annual

[zav6a]

I?ve looked, perhaps not exhaustively, for best practices for testing alternators at annual inspection. Essentially nil. Given growing dependence on our electrical systems, I?m somewhat surprised.

I?ve been hooking up an oscilloscope occasionally and checking the waveform of the alternator ripple. Once you do it a time or two, and diagnose a few of your kid?s broke down cars, it is fairly simple and obvious what is good and bad. It also provides some peace of mind knowing that all of your diodes and windings, not just enough to get you by, are functional.

These tools are now cheap and easy to use. I can?t think of a reason not to incorporate this element into our annuals and diagnostic processes for electrically dependent planes. Like boresopes, scales, RF equipment testers, there ought to be one and someone who knows how to use it, at every Vans based airport!

[Ironflight]

Sounds interesting Duane - how about writing up a guide for what to look for - what’s a healthy one look like? What’s a dying one look like?

[zav6a]

I actually thought while posting ?Just watch, Paul or Dan H. will say, put your money where your mouth is?.

I?ll start compiling screenshots and when I have useful sampling, I?ll get back to you.

[Ironflight]

Originally Posted by zav6a

I actually thought while posting ?Just watch, Paul or Dan H. will say, put your money where your mouth is?.

I?ll start compiling screenshots and when I have useful sampling, I?ll get back to you.

Great! I?ve been looking for an excuse to buy one of those USB scopes.....

Paul

[Mike S]

I never thought about using a scope----but I was taught to loosen the belt, and spin the pulley, feel for rough spots, push/pull to check any bearing looseness etc.

[rv6ejguy]

Originally Posted by zav6a

I actually thought while posting ?Just watch, Paul or Dan H. will say, put your money where your mouth is?.

I?ll start compiling screenshots and when I have useful sampling, I?ll get back to you.

Looking forward to your data. Have you seen evidence of diodes slowly breaking down over time or simply complete failure of them?

[mike newall]

Originally Posted by Ironflight

Sounds interesting Duane - how about writing up a guide for what to look for - what?s a healthy one look like? What?s a dying one look like?

Duane,

Writing a technical article for an esteemed and edumacational magazine should be charged out at Union rates....... say $10 a line

[zav6a]

Ross, data set is limited to 40 years ago as a Yamaha tech they taught use of a scope and more recently as a home mechanic working on my kids clunkers. It that time I?ve never seen a partial failure of a diode. I have seen bad solder joints of both windings and diodes.

Gosh, if that is the going rate, I don?t think I can afford to write an article. Maybe the editor will give me a discount.

[noelf]

I have had articles published in both SPORT AVIATION and KITPLANES magazines. KITPLANES does pay the author for the published articles, but not $10. / line. To me, I was surprised to receive any compensation and it was not expected.

[zav6a]

I should quit any attempt at humor.

I come from a professional field where it is hard to get published. Hence the joke about having to pay Paul off.

In all seriousness, if I get adequate content together, I?d be honored to contribute.