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Capacitor ESR values. What do you think?

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fastline

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I am working on a drive circuit for a small refrigerator. The fridge fans would come on for about a sec, then go off, and repeat continuously. I suspected an unstable circuit. I tested all the large caps but everything was in spec. I then started testing the small value caps and found a couple that are high. The board has about 8 of the same cap which is 4.7uf/50V. Most test in the 3-5 ohms range with the ESR meter. The two suspects are testing 35 ohms and 95 ohms. These have all been pulled from circuit to verify.

I then checked them with with my cap meter and they test GOOD... I would really like some experience to chime in and confirm what I am seeing here. There is also a small pf ceramic cap in that area that would not test at all with the ESR meter but testing at .1nf with the cap meter. 102k 1kv is what is on it
 
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With out the part number I cannot look up the data sheet. There should not be a 10:1 difference in ESR. Relpace the two caps.
 
Personaly I would replace the 2 that read 35/95 ohms. The reason they now test ok is probably because you disturbed them removing from circuit & heating them desoldering.
 
Thanks!!!! I word of praise for my new ESR meter!! Replaced the said caps and we have a functioning circuit now! I will admit that I had some doubt of the meter. As well, I just schooled myself a bit because I have never run into a small electrolytic that failed, usually only the big filter caps. WOW. Always exciting to fix something and who else could I gloat to about my meter other than you guys??? Hell, no one else even knows what one is...
 
Thanks!!!! I word of praise for my new ESR meter!! Replaced the said caps and we have a functioning circuit now! I will admit that I had some doubt of the meter. As well, I just schooled myself a bit because I have never run into a small electrolytic that failed, usually only the big filter caps. WOW. Always exciting to fix something and who else could I gloat to about my meter other than you guys??? Hell, no one else even knows what one is...

Now you should post the Model # with a reference to the problem and solution. It would be good to take a picture of the board. Someone else on the net with no money and just time and an ESR meter will give you praise for the rest of the "threads Life" :)
 
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ESR meters are important to me & ive built & use 2. The grey one is the Mk 1 version & ive built the Mk2 version.
 

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