[dougknight]

Is anybody doing their own 500 hr inspections on their magnetos? If so what brand of meter are you using to check the capacitor? Are some of the $40-50 dollar range meters adequate or do they have to be checked on something much more sophisticated such as the GenRad Digibridge component Analyzer and a Megohmeter?. I have slick 4300 series magnetos.

thanks
doug

 

[N804RV]

You need the megger to test for the minimum of 50Gigohms between the capacitor stud and the shell at an applied 135VDC. A multimeter just won't do that.

The capacitance should be measured at 1khz test frequency. Its important to measure the capacitance under the specified conditions. Low freq caps have a nasty habit of testing just fine on the bench and then quickly failing under actual operating conditions.

I've been looking for the capacitor test specifications for my old trusty Fluke 77/III and can't find it.

 

[flightlogic]

Second that. A common DVM will not be able to properly test them.
A high dollar test may be next to useless also.
They will fail in operation after a pass.
Like doing a stress echo cardiogram. You can drop dead in the parking lot after a pass from the doc. Not too expensive to replace though... if suspect.