Calibration of bridge standard for strain gauge bridge amplifier
David Corminboeuf · 17th International Congress of Metrology · 2015
This paper presents an automatic system developed at METAS for the calibration of bridge standards used as reference for strain gauge bridge amplifiers. This system, based on a comparison method, uses a PXI chassis with two acquisition boards to balance the bridge automatically. The use of two specific inductive voltage dividers is required to reach the very high accuracy of this type of bridge standard. With a ratio of 2 mV/V, an input voltage of 10 V at 225 Hz, the relative uncertainty is 8 ppm, which is 16 ppb of the input voltage.