Advances In Technique of Lightning Measurements

Improved measuring equipment and refinements of technique contributed materially to the number and accuracy of lightning records taken, in a 4-year study, on a rural distribution system. Special shunts were developed to match the expected lightning currents to the voltage graphs. Modifications were made in the method of initiation of the oscillographs and in their operation so as to get the greatest possible accuracy and to extend their period of unattended reliable operation. Refinements were made to increase the accuracy and speed of magnetic link calibrations and to permit the calibrating equipment to be operated from a low-power 115-volt supply. The 60-cycle after effects of lightning disturbances on the system were recorded by an automatic magnetic oscillograph.