The leakage of typical ceramic caps is too low to view on a curve tracer. A capacitor meter or impedance bridge is the right tool for the job. All capacitors have leakage, but most have leakages too low for most people to measure. It is more typical to measure capacitance and D (dissipation factor) or ESR at a specified frequency, possibly with a bias voltage (many caps with type 2 dielectrics have horrible voltage coefficients, with Y5V dropping C by 80%).
If you tell me the specified leakage and voltage rating of the part, I may be able to suggest an easy to measure the leakage with a voltmeter and a DC power supply.
Later,
Carl
Carl B. Van Wormer, P.E., AE7GD
Senior Hardware Engineer
Cipher Engineering LLC
21195 NW Evergreen Pkwy Ste 209
Hillsboro, OR 97124-7167
503-617-7447x303
[log in to unmask] http://cipherengineering.com
-----Original Message-----
From: [log in to unmask] [mailto:[log in to unmask]]
Sent: Friday, August 19, 2016 7:39 AM
To: Carl Van Wormer <[log in to unmask]>
Cc: [log in to unmask]
Subject: RE: Techtronic 576 Curve Tracer
I am trying to find out if SMT ceramic cap has leakage. We do have a control part for reference. I need guidance in 576 control knob selection and setting. Again I have no experience in checking a capacitor with a curve tracer. Our LCR bridge is out for cal. I do recall an oval shape output.
Victor,
-----Original Message-----
From: Carl Van Wormer [mailto:[log in to unmask]]
Sent: Friday, August 19, 2016 9:27 AM
To: TechNet E-Mail Forum <[log in to unmask]>; Hernandez, Victor G <[log in to unmask]>
Subject: RE: Techtronic 576 Curve Tracer
Curve tracers can display a variety of ovals ranging from flat lines (at various slopes) to circles. The results depend upon the settings of the curve tracer and the characteristics of the capacitor. Curve tracers can be best used if you have a known good part and want to see if another part matches the good part under the conditions of the applied voltages and measured currents. If the displayed waveform doesn't match, the parts are different. Determining that a single part is good is more difficult. For a capacitor, you would expect smooth curves or straight lines without bends or kinks. Curve discontinuities would indicate a voltage breakdown, possibly because of reverse polarity problems. You can use the curve tracer's higher voltage ranges to intentionally break down caps, and may be surprised how high a voltage a capacitor will take (for short times) without breaking down.
Is there a particular test that you are trying to perform on the ceramic capacitor? My co-worker's favorite question is "What is the problem that we are trying to solve?"
Later,
Carl
Carl B. Van Wormer, P.E., AE7GD
Senior Hardware Engineer
Cipher Engineering LLC
21195 NW Evergreen Pkwy Ste 209
Hillsboro, OR 97124-7167
503-617-7447x303
[log in to unmask] http://cipherengineering.com
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Victor Hernandez
Sent: Friday, August 19, 2016 7:10 AM
To: [log in to unmask]
Subject: [TN] Techtronic 576 Curve Tracer
Fellow TechNetters:
Has anyone out there have experience in using the above stated tester to check a ceramic package capacitor. All comments suggestion welcomed. I believe the screen would display an odd oval shape.....
Victor,
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