Calibration of Charge Amplifier on Vibration Acceleration Standard

Abstract

The calibration procedures of charge amplifier (CA) on vibration acceleration standard are described. The calibration principle and fundamental calibration procedures are explained in detail. Typical commercial CAs (3 types, 4 CAs) are evaluated in terms of the frequency sensitivity gain, the long-term stability, the linearity for input charge, the linearity for gain setting and the effects of environmental conditions (temperature and humidity). The maximum discrepancy in the sensitivity gain is approximately 4 % among the tested CAs. A relative sensitivity gain difference of 1.5 % still remains when CAs of the same type are compared. It should be mentioned that a difference of 1.5 % is not negligible. Such a large difference has not been commonly observed up to the present time. Based on these experimental results, the technical guides for charge amplifier calibration are summarized.