These parts age like crazy and low rated parts can age 7-10% per decade hour? Hour .1, 1, 10, 100 etc.
Your IQC needs a procedure to de-age the parts at 150C and then test.

John 

Sent from my iPhone

> On Jul 18, 2018, at 8:49 AM, Stadem, Richard D <[log in to unmask]> wrote:
> 
> Check to see if the capacitors are counterfeit.
> 
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Guy Ramsey
> Sent: Wednesday, July 18, 2018 7:00 AM
> To: [log in to unmask]
> Subject: [TN] capacitor measurement
> 
> I got pulled into a Receiving Inspection problem. Our test instrument, an
> old HP 4192A impedance meter, and a newer Instek 6020 tell us that our X5R
> capacitors are out of spec.
> A 100uF, 10%, 6.3V capacitor measures between 25% and 30% below the nominal
> value.  The instruments have Kelvin probes and are zero calibrated at
> frequrency, 120Hz the test waveform is 500mV rms.
> Does anyone have any advise?