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Rotating Diodes Checking

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Old 11-12-2017, 02:03:58 PM
len k len k is offline
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Default Re: Rotating Diodes Checking

YD electronic reg has 2 SCR, magnaciter only diodes.

Only true way to test a diode is take it out of the circuit and test, can have a max of ONE circuit connection to it remaining. I like using an analog meter, once you test a good diode you'll see the pattern of a good one. The resistance while conducting all seem to fall in same meter deflection position.

But may times in other electronics you can still see that it's acting as a diode even though it's still in the circuit. Guessing with windings resistance of winding is so low you'll have to take it out of the circuit to test it

Last edited by len k; 11-12-2017 at 02:16:40 PM.
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Old 11-12-2017, 09:04:04 PM
armandh armandh is offline
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Default Re: Rotating Diodes Checking

old as time
replace vs repair

for a business
a known replace is easier to sell and do

for a hobby time is not that critical
and likely lower cost
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Old 11-13-2017, 05:52:47 PM
Jim Marcozzi Jim Marcozzi is offline
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Default Re: Rotating Diodes Checking

Once I verify that the diodes are good with an analog ohm meter, I always load them with about half their rated amperage with a lamp in both directions.

I've found many diodes over the years that check good with a meter, but break down under load. With gen end diodes, I usually use a halogen headlight bulb. Under load, I like to see no less than .7-1.0V max drop when comparing the voltage at the load to the voltage at the source.
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