In 1943 the first 138-kv. underground power transmission cables west of Chicago were installed by the Los Angeles Department of Water and Power.1 This double-circuit cable line, about five miles long, extends from Nichols Canyon in the Hollywood hills, south through Hollywood along Fairfax Avenue to Receiving Station “D”, on Venice Boulevard. (See Figure 1.) The cable line represents a considerable investment and is an important link in the transmission system, so it is essential that the cable sheaths be protected from electrolysis, since the useful life of these cables is fixed by the life of the lead sheaths.
After considerable study, and numerous electrolysis tests, two cathodic protection units were installed on the line. Later, two more units were added, and this protection was extended to coyer six 34.5-kv. cables which cross and parallel the 138-kv. line.
In each circuit of the 138-kv. cable line there are...
