A Device to Determine the Number of Turns and the Presence of Short-Circuited Turns on Cylindrical Coils

A device to measure the number of turns and the presence of short circuits between turns is described. It will measure, depending on the construction of the magnetic comparator, cylindrical coils with or without a ferromagnetic core. The accuracy for the number of turns measured is ± 0.1 per cent. Short-circuited turns, either intentional or accidental, affect only slightly the accuracy of the measurement of the number of unfaulted turns only slightly. On coils without an iron core, the presence of one short-circuited turn of No. 25 AWG copper wire can be detected.