DE5000 odd reading

[ImpulsiveJames]

I purchased a DE5000 to test a lot of capacitors from an amplifier. They are all 4700uf 100v. Most of them are reading 4500uf, which I'm expecting is normal from 15 year old capacitors.

My question is, one of them is reading 1pf with the DE5000, but 4800uf with a cheap honeytek meter.

What could cause this? I know the cap is junk, but I'm just curious why there is such a difference and how they could be so far off.

[Dr. Frank]

Hopefully, you always have properly dis-charged the capacitors, before measuring them with the DE5000.
Otherwise, you might have damaged the instrument by over voltage.

Please check your both devices with a known-good capacitor.

If both still work, the difference might be due to very different measurement techniques.
Also, try different frequencies and parallel / seriell capacitance modes.

Frank.

[wraper]

Lower the frequency. It should be 120 or 100 Hz.

[Martin72]

They are all 4700uf 100v. Most of them are reading 4500uf, which I'm expecting is normal from 15 year old capacitors.

Such a value would also be normal for new electrolytic capacitors, as their tolerances are usually 10 or 20%.
Unlike in e.g. switching power supplies, electrolytic capacitors in an (audio) amplifier have an almost paradisiacal life, which can last a very long time if the ambient temperature is not high.