FIELD: electric safety engineering for power installations.
SUBSTANCE: proposed method for identifying AC or DC voltage across current-carrying parts of power installations is characterized in that prior to taking measurements reference voltage is applied to internal metering circuit of measuring instrument to convert its signal indicating its serviceability and readiness to take measurement into light signal. Additional external metering circuit is organized for the purpose using contact principle of voltage checkup by which resultant voltage is recorded and its parameters are analyzed; if resultant voltage parameters coincide with those expected across current-carrying part of power installation under check, resultant voltage is converted into voltage indicating signal which is passed to energized condition indicator; if resultant voltage parameters coincide with reference voltage parameters, it is converted into no-voltage indicating signal; used as the latter is signal indicating serviceability of measuring instrument and its readiness to take measurements; if resultant voltage parameters do not coincide with those of reference voltage nor with parameters of voltage expected across current-carrying part of power installation under check, resultant voltage is converted into no-voltage signal which is supplied to no-voltage indicator.
EFFECT: enhanced precision and reliability of identifying energized or non-energized condition of power-installation current-carrying parts.
1 cl, 1 dwg
Authors
Dates
2007-02-20—Published
2005-07-28—Filed