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I realize .077n translates to 77p but is there a reasonable explanation why they would test so far out of spec?

I'm using a Crenova 890Z DMM. Is there another way to test them, other than on the capacitance setting?

All my other "p" caps test fine as well as all other types of caps. But these are a head scratcher.

I have 2 separate bags of these 47p's and all of them are reading .077n-ish.

Any thoughts before I contact the vendor?

Thanks!

~Troy

I don't know that meter...does it have a button like REL or RELATIVE or something like that?

You sometimes have to use that (if it has one) when testing small value caps to get it to ignore the capacitance of the test leads. I'd check your manual and see if it has something like that.

Hey Chip. Thanks for chiming in.
No such buttons on this meter. However, I did come across this fine print in the user manual: "You may have to subtract the distributed capacitance of the lead wires for accurate measurement of small capacitors."

So I guess that's what has to be going on here.
There is just no other explanation for why this is happening to these small caps. I suppose I just have to assume they are within spec since they all test within a few thousandths of each other.

~Troy

FWIW, that seems like a very reasonable assumption to me.

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Yeah, if they're all that similar, I think you're probably good.

It doesn't seem crazy to me that a couple feet of lead wire might have 30pf of innate capacitance.

Right on! Thanks gentlemen!

-Troy

Using your same setup, test two of them in parallel, then three in parallel (and more if yer really bored). By how much does the reading increase every time you add another one in parallel?

For that matter, what does it read when you have leads in but NO explicit capacitor?

Damn, never even thought to try any of that...DOH!


When I return to me bench tonight, I will post back with the findings.

Thanks WMP1!
~Troy