1907 - 75kV from Kern River

Edison Electric Co. of Los Angeles, CA built the 27,000 horsepower Kern-1 plant downstream from the 1903 Borel plant. The 117-mile transmission line to Los Angeles was the first in the western United States to be supported on steel towers. To withstand the record 75kV transmission voltage, a new insulator was designed, now known as the M-4800. These were primarily supplied by Locke’s VICTOR brand, but when Locke could not ship enough to finish the project on schedule, a number were ordered from Thomas and New Lexington as well. The units are impressive - 18in. diameter top, lily-shelled second and third skirts, all cemented onto a massive steel pin. The picture at left was taken in 1907, looking south up the “Grapevine,” where Interstate 5 now enters the Tehachapi Mountains. We were able to recover all three types of M-4800 from the line over the winter of 2002-2003 and showed them at the 2003 Springfield NIA National. The story is posted on Elton’s r-infinity.com web site.

VICTOR M-4800

THOMAS M-4800