Cathodic Protection Training Course


Module 12

Long term monitoring

Installed monitoring using sacrificial anodes.

A sacrificial anode is installed to increase the electrical potential of the ground thus causing charges from the decay of the anode to enter the pipeline or structurein opposition to the charges that would otherwise pass from the subject metal into the electrolyte.

Charges from the subject metal dissolve metal at a rate related to the current (Farraday).

Monitoring a sacrificial anode using a sensitive current meter (Micro-ammeter) should show current passing FROM the anode into the ground when the impressed current coathodic protection is switched off and this direction should reverse when the impressed current system is switched on.

This effect can also be seen when conducting DCVG and CIPS surveys when the Cu/CuSO4 ground contact electrode is over the location of the sacrificial anode.

Students will be required to provide a summary and examples.
for on-line real-time discussion.