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Multimeter | Clamp meter | Insulation Resistance Tester | Panel Meter | Oscilloscopes | Test leads & Accessories | Software Updates => Bench-top multimeter => Topic started by: Kiriakos GR on June 13, 2019, 08:07:58 PM

Title: Fluke 8846A capacitance measurement at Highest Precision down to Pico Farad
Post by: Kiriakos GR on June 13, 2019, 08:07:58 PM
No matter if Fluke 8846A (DMM4050) this is a remarkable in quality and precision instrument, when it has to do with capacitance measurements’ down to Pico Farad, this requiring some help so to perform at it best.

Originally I did a web search so to discover if any manufacturer made the thought to create a special accessory for benchtop DMM, so this to be a dual banana with slots at the back as clips for capacitors installation.
Then I thought to use K-type plug convertors which I all ready have and I made the discovery that it works great for testing of unused capacitors with long leads.

This afternoon I also added in my collection a new accessory, the concept this is again an original idea of my own.
Originally I was having in my hands (a Made in Japan) Mains adapter, and then I did removed common pins and replaced them with male banana, pins spacing this is compatible with DMM input spacing.
Now I am ready to move this idea much further, but I am not going to get in details right now.  8)

Fluke 8846A this extremely capable for capacitance measurements, in theory it is enough the user to perform ZERO (math) for test leads capacitance removal.
But for truly Highest Precision at few Pico Farad you should stop using test leads and to improvise by following a better approach as I did.

My Fluke 8846A this add about 2~3 Pico Farad with out anything connected at the input terminals.
My workaround this is to plug-in this K-type plug convertor, then to use Zero (Math) and then to install the capacitor at the back of the convertor.

I did take several pictures for you to see and personally I am extremely satisfied from my results so far. 
I do not do anymore RF work and DIY Oscillators’, but I am going to use my new experiences at DMM calibration verification applications.   :)