A Low-Frequency Thermal Follow Bridge for Measuring the Electro-Thermal Parameters of Bridgewires

摘要

Advances were made in the art of measuring, nondestructively, the electro-thermal parameters of wire bridge electro-explosive devices. In particular, the thermal-follow phase-shift bridge was redesigned to operate at lower frequencies (approximately 10 Hertz instead of the previous 60 Hertz). Fourfold increases in resolution and accuracy are typical of the lower frequency. Two circuits are described one being battery powered and the other powered from AC mains. Experimental data obtained on one of these circuits are included to show how clearly these measurements detect the presence of explosive in contact with the bridgewire. (Author)