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Image Credit: All-Spec | Allied Electronics | Metric Test

 

Capacitance meters are instruments that measure capacitance, the ability to store an electric charge. They are used to test, inspect and sort ceramic and other types of capacitors on production lines. In addition to frequency, capacitance meters are specified according to measurement parameters.

 

Capacitance Meter Specifications

Product specifications also include:

  • Display range
  • Test voltage
  • Accuracy
  • Measurement time 
  • Compensation
  • Interface types
  • Measurement speeds: short and long. Short-mode devices provide capacitance measurements more quickly, but are not accurate as long-mode capacitance meters. 
  • Cable length
  • Measurement signal frequency
  • Averaging range and resolution
  • Time modes
  • Trigger modes
    • Internal and external trigger
    • Trigger delay time
  • Display time

    • Display renewal timing

Measurement Parameter

Capacitance meters carry measurement parameters Cp-D, Cp-Q, Cp-Rp, Cp-G, Cs-D, Cs-Q and Cs-Rs.

  • Cp equals the capacitance value measured with the parallel equivalent circuit model.
  • Cs is the capacitance value measured with the series equivalent circuit model.
  • D, the dissipation factor, is a value that represents the tendency of an insulating or dielectric material to absorb some of the energy in an AC signal.
  • Q, the quality factor, is the inverse of D.
  • G is the equivalent parallel conductance measured with the parallel equivalent circuit model.

  • Rp is the equivalent series resistance measured using the series equivalent circuit model with capacitance meters.  

Capacitance Performance Specification

Performance specifications for capacitance meters include

  • Allowable frequency range and accuracy
  • Level range resolution and accuracy

  • Output impedance at both 1 KHz and 1 MHz

Functions

Functions are often described as compensation, comparator, data buffer, deviation measurement, low-C reject, and save or recall. Capacitance meters also carry specifications for power source, operating and storage environment, and product weight. 

 

Approval Organizations

Capacitance meters may bear marks from various national and international approval organizations. For example, the European Union requires CE marks for all electric and electronic equipment that will be sold, or put into service for the first time anywhere in the European community. Capacitance meters that bear a CSA Mark have been tested by the Canadian Standards Association (CSA) and meet applicable standards for safety and/or performance. These standards are written and administered by organizations such as the American National Standards Institute (ANSI), Underwriters Laboratories (UL), and CSA International. The International Electrotechnical Commission (IEC) also prepares and publishes standards for capacitance meters.