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I recently bought the De5000 LCR meter and have been measuring some components I have on hand to get a feel for the meter.

Measuring electrolytic and Mylar capacitors have given reasonable ESR values based on their data sheets yet when I measure the ceramic capacitors I have on hand they read ~10-100 ohms of ESR. I am measuring them using 10/100Khz as specified as the most accurate in the data sheet for the capacitor values I am using -- 22pf to 22nf.

Is this typical of cheap ceramic capacitors? I don't have the data sheet as I bought them from some Chinese ebay store. Could I just be measuring them wrong?

Thank you for your help.

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    \$\begingroup\$ Sounds within expectation from cheap chinese ebay stuff \$\endgroup\$
    – PlasmaHH
    Dec 14, 2015 at 22:31
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    \$\begingroup\$ It doesn't sound reasonable to me, it would seem to me to be hard to get 10s of ohms of ESR in a ceramic capacitor, even a cheap one. But without a datasheet or any real information at all it's difficult to say for sure. \$\endgroup\$
    – John D
    Dec 14, 2015 at 23:11
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    \$\begingroup\$ No data sheet equals crappy component. I've said this a few tines but don't buy stuff without a recognized PDF data sheet. \$\endgroup\$
    – Andy aka
    Dec 14, 2015 at 23:12
  • \$\begingroup\$ @Andyaka -- although sometimes, that's no guarantee -- I've seen PDF datasheets for connectors that don't ID which contact corresponds to which pin :P \$\endgroup\$
    – ThreePhaseEel
    Dec 14, 2015 at 23:18
  • \$\begingroup\$ I wasn't expecting much of them, but i expected the ESR to at least be better than what I'm measuring. I am aware buying things without datasheets isn't a good idea but they were cheap and for basic circuit applications I figured they'd be fine. Lesson learned. \$\endgroup\$
    – Andrew Cragg
    Dec 14, 2015 at 23:50

1 Answer 1

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After some digging around on Digikey I think I found my answer. These caps appear to be the Z5U type. I looked at data sheets from various manufacturers and have found that for this type the dissipation factor can be as high as 4.5% which gives me theoretical ESR values very close to what I actually measured.

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