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Old 10-30-2010, 01:22 PM   #3941 (permalink)
Weisheimer
Mark Weisheimer
 
Join Date: Aug 2009
Location: Columbus Ohio
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Darlington Power Modules

Quote:
Originally Posted by snakub View Post
Does anyone have a board lying around maybe you could do some testing like I did and tell me what measurements you got?
My spare board was not a populated as I thought....
But I'll share some thoughts.

Quote:
Originally Posted by snakub View Post
I still think the issue is in the control board here are some oddities that I found while measuring components while they were on the board.
I would take the control board to the bench and test it.
Do you have an o'scope available? It would be quite helpful.
If you can't test it there, mail it to Columbus and I'll promptly test
it and send it back to you.

Quote:
Originally Posted by snakub View Post
D8 and D9 are not backwards but I couldn't test them properly either when I measured them with the multimeter positive to positive negative to negative I got 7.3k both ways.
Your multimeter should have a diode test. It will read about .7v one direction and 0L when the leads are reversed.
The multimeter has to provide at least enough voltage to overcome the diode threshold. If you have already tested it with that scale, then the diodes are faulty.
They are not located in a place where I would expect them to fail from an external fault, so I expect them to be OK.

Quote:
Originally Posted by snakub View Post
R18 measured 2.2k but I looked at it and the color code was definitely Orange black red 100 percent sure.
It is probably fine, the other components are causing that reading.

Quote:
Originally Posted by snakub View Post
Maybe I have to take these parts off to get a proper measurement?
Yes, in theory, but other than your diode measurements, they seem
OK to me.

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