Establishment of 4TP air-dielectric capacitance standard for 1 pF, 10 pF, 100 pF and 1000 pF in the frequency range up to 30 MHz at NIMT

The 4TP air-dielectric capacitance standards have been evaluated successfully for the establishment of metrological traceability of capacitance standards at high frequency, and also the calibration measurement capabilities are suitable for supporting customer needs in Thailand. The approach used for the evaluation is to find all resonance frequencies of 4TP air-dielectric capacitance standard using scattering parameter measurements employing a precision network analyzer. Inductive residual parameters of C4TP are calculated from these resonance frequencies, and capacitive residual parameters are measured by using a 1 kHz capacitance bridge. Finally, the C4TP is calculated from electrical-equivalent circuit model after all residual parameters are known.