PROGRESS IN MEASUREMENTS WITH THE ETF VOLTAGE BALANCE

The results of two series of measurements with the ETF-84 voltage balance carried out in 1987 and 1988, using the classical method of ''weighing,'' described in [1] were presented in [2] with the proviso that some systematic errors had not been accounted for. Detailed analyses of these errors are now in progress, as are numerous experiments to determine the possible corrections and to estimate their uncertainties. Some of these cannot now be determined exactly, especially those that are due to time-dependent irreversible processes. To eliminate such effects and to achieve the most accurate possible determination of the volt, a new method for measuring the capacitive current when moving the high-voltage electrodes with a constant speed has been established. In this method, there is no need to measure the ac capacitance between the electrodes. The results achieved with the new method are promising, and we expect to report on them before or at CPEM '94.