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So I found out that my DMM maximum reading is 100uF (Though its price is twice the ones that reads upto 100mF, mostly because its 8 years old). It doesn't have manual range for capacitance measurement, it's auto range (From 50nF to 100uF).

Now I have capacitors (that I need to check) their values starts from 100uF : 470uF. When I tested a new capacitor (100uF 16v) it showed me 0.18nF, when I tested a used capacitor (470uF 450v) it showed me 0.18nF too.

How can I tell if they're good using other DMM tests?

P.S: None of them are bulging, still they could be bad, that's why I need to check their readings.

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If your meter's limit is 100 uF then you could measure the 470 uF by putting it in series with a 100 uF. The net capacitance should be: -

$$\dfrac{1}{\frac{1}{100uF}+\frac{1}{470uF}} = 82.46 uF$$

And this should be in the range of your meter (providing it can measure electrolytic capacitors correctly). Of course, many electrolytic capacitors can be up to 80% higher than their marked value so what you really need is a good reference point for capacitance; maybe use two 100 uF capacitors in series and see what that gives you as a reference. It should be 50 uF but could be as high as 90 uF.

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