LIGHTNING — PEEK 



187 



20 



30 



2&V> 



40 60 80 100 



SPARKING DISTANCE IN INCHES 



120 



140 



00 



Lightning Spark-over Curve between Points 



Fig. 23 



X 100 



s 



b. 



° 80 



^ 60 



t3 40 



20 



5 



004 



08 



0.12 016 0.20 0.24 



TIME IN MICRO-SECONDS 



0.28 0.32 



0.36 



Fig. 24. — Wave sshape of lightning used in the tests. Wave shape No. 1. Two 

 million-volt impulse generators 



