A New Current-Sensing Device

Development of a reliable, low-cost current sensing device was undertaken for use in capacitor switching, load study, and protective relaying. The unit takes the form of an inductive pick-up coil imbedded in a porcelain insulator. It may be used on straight conductor runs with an accuracy of ±6% before applying correction factors which depend on physical configuration and size of conductor. Output impedance is high, suggesting use of high-impedance loads. Sufficient power is available to operate electronic equipment and sensitive relays.