DIFF Subgroup
G01R 31/081 Full Title
Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere ( testing line transmission systems H04B3/46; testing or measuring semiconductors or solid state devices during manufacture ) > Locating faults in cables, transmission lines, or networks
Of 3 combined children, 0 exist in both systems.
3 codes are CPC-only extensions.