Capacitance Standards

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Capacitance Standards

 

standard (electrical) capacitors, characterized by highly stable nominal capacitance (constant calibration). Such standards are used mainly for accurate measurements conducted with capacitance meters and q-meters. Capacitance standards are divided into two groups: (1) constant capacitance of 0.5 pF (picofarad) to 0.1μF and (2) variable capacitance of up to 0.002 μF. The dielectric in the standards is usually a high-grade mica, a ceramic with low dielectric losses, and air. The temperature coefficient is usually 10-5-10-6 deg-1 and the loss tangent is tan δ = 10-3-10-4. Measures of capacitance are carefully shielded during accurate measurement in order to reduce any capacitive coupling with surrounding objects.

REFERENCE

Valitov, R. A., and V. N. Sretenskii. Radiotekhnicheskie izmereniia. Moscow, 1970.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
NIST plans to transfer the frequency dependence data to the Farad Bank and other reference capacitance standards, so that in the near future, improved capacitance calibrations will be available from NIST for the entire audio frequency range.
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