We have some block valve facilities installed along the 24” crude pipeline and the electric actuator of the valve is connected to earth grid of 15 meters long and 15 meters wide located 1.6 meters below the protected pipe.
The potential measure between pipe (inside the concrete walls) and soil...
I am the in-charge to construct a small electrical facility in sandy area and the maximum acceptable (permissible) value for protective earth system is 10 ohms. For the first earth pit I use a copper rod 15mm diameter, 5 meters long in a hole 100mm diameter filled with Marconite/cement mix but...
