busbar
Electrical
- Apr 12, 2001
- 2,644
I am retired from a weapons-test site where, for safety concerns, every building, bunker and magazine has a ground ring of 4/0-AWG copper conductor directly buried, encircling each—with ¾”x10’ copper-clad rods at corners. Early on, {1950s to 1970s} seven-strand conductor was used, but later contractors got away with installing more readily available nineteen strand.
The soil there is immensely corrosive, and concerns are that 19 strand has a greater surface area exposed to corrosive soil than 7 strand. Figure (7/19)^0.5 = 0.61 per-unit—thus 7 strand has 39% less surface area than 19 strand.
My question is, in this application, should 4/0-AWG 7-strand conductor perform appreciably longer than 19 strand?
The soil there is immensely corrosive, and concerns are that 19 strand has a greater surface area exposed to corrosive soil than 7 strand. Figure (7/19)^0.5 = 0.61 per-unit—thus 7 strand has 39% less surface area than 19 strand.
My question is, in this application, should 4/0-AWG 7-strand conductor perform appreciably longer than 19 strand?