Question

3. a Calculate the current output for a 17 pound packaged magnesium anode buried in a 1750 ohm-cm soil for the protection of a bare pipeline where the expected resultant pipe-to-soil potential is -0.80 V (SKK 2.2.4, 20%) b. Described the undesired current which the metallic structure placed underground Mentioned and clantied these undesired current ((SKK 226,10%)

Answer 1

a) The current output can be calculated by: $I_m = \rho * f* Y$

here V is the potential given -0.80 V

$\rho = 1750 \Omega-cm$

corresponding to the weight of Magnesium i.e. 17 pounds

f corresponding to magnesium of 17 pounds is 1.

And the potential correction factor Y is -0.85

Hence Im is -1487.5 mA.