| 摘要 |
FIELD: measurement technology. SUBSTANCE: resistance tester is related to devices for timely measurement of resistance in D C networks with common minus bus, for instance, in locomotives. Technical result of invention consists in increased accuracy and authenticity of measurement results thanks to absence of resistance coupling between measurement object and adjusting part of tester, thanks to decreased number of resistors and influence of their state. Essence of invention lies in that zero magnetic flux is gained by automatic adjustment of currents in two coils of tester with use of compensation principle of their magnetic fields by circuit of bridge type. Tester incorporates reference resistor, voltage-to-current converter, threshold element, resistive divider, digital-to-analog converter, analog-to-digital converter and magnetic flux sensor connected in adjustment circuit. EFFECT: increased accuracy and authenticity of measurement results. 1 dwg |
