抄録
Two fully-automatic mass comparators housed in each airtight chamber have been installed for simultaneous calibration of the mass and the volume of weights in the range from 1 kg to 20 kg. One is a 10-kg mass comparator having a readability of 0.01 mg and the other is a 20-kg mass comparator having a readability of 0.1 mg. These mass comparators are equipped with a four position weight exchanger, and carry out automatic mass comparison. The chambers can keep air density constant at a fixed value with in the range from 0.6 kg/m3 to 1.2 kg/m3 by changing its internal pressure from 60 kPa to 102 kPa, and thereby the mass and the volume of a test weight can be simultaneously evaluated. In this paper the features and results of performance tests of the mass comparators are described.
