Arta\Limp strange artifacts during capacitance measurement

mecedo

Member
2019-01-24 8:35 pm
I'm trying to setup my measurement system for Arta but I have one problem. There are strange artifacts on phase graph during capacitance measurement. Value of capacitor is measured correctly, only resistance is 5-10x higher then it should be. On resistors and inductors there's no problem. Values are ok and charts are clean.
I've tried to use three different computers with integrated Realtek audio cards and additionally in one computer I've installed SB Live Digital 5.1. Always the same result. I've tried different reference resistors: ceramic or noninductive. I've tried with good quality Klotz microphone cable too. I've checked cables with DMM and connections and values are ok. System is calibrated correctly as in user's manual. I've measured card with loopback cable and parameters are quite decent. I'm using electric terminal block to connect measured elements so connection is firm and solid. Measure averaging helps to clean phase on chart but only a bit in higher frequency range.
I can't find the reason of the problem. Have you encountered similar problem with capacitance measurement?
 

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  • 3 capacitor.jpg
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  • ARTA THD.png
    ARTA THD.png
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  • ARTA FREQ.png
    ARTA FREQ.png
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