The efficiency of the cathodic protection of pipelines is conventionally determined by the potential readings obtained from the designated Test Posts placed regularly in every 1-2 km. While this is very useful information the Test Post potential readings only represent less than 1% of the pipeline surface. The Test Post data does not provide any information on the pipe to soil potentials at a distance from the Test Post.
During the CIPS measurement the pipe to soil potentials are measured and recorder in every 1-2 m whilst walking along the pipeline route on the top of the soil.
All the cathodic protection stations affecting the inspected pipe section are simultaneously interrupted and the structure and polarized potential of the pipeline are measured and recorded with a synchronous datalogger (computerized voltmeter). The measurement takes place automatically.
The measured values and data considered as important will be stored in the memory. During later processing we make a potential diagram using this data. From the diagram the efficiency of the cathodic protection can be determined along the whole length of the pipeline.