³Ô¹Ïtv / TESTING AND PROTECTIONIn-circuit resistance can include parallel pathsR1R2Two paths between the same nodesTwo ideal resistors share thesame nodesEquivalent = 1 / (1/R1 + 1/R2)Real circuits may includenonlinear devicesThe model is not a componentfault diagnosisExplanatory schematic / not an inspection record or released drawing