This formula considers the attenuation of the pipe to determines the required structure voltage based on the current output.
Rudenberg’s formula is very theoretical just using pipe parameters. Other factors to be considered include the presence of foreign metallic structures, accessibility and availability of a power source which are not included.
Vx — Potential at X in volt caused by grounds anode current
I — Ground anode current(Amps)
ρ — Actual soil resitivity (0hm / cm)
y — Length of anode in earth(ft)
x — distance from ground anode(ft)
If x > 10y then,