Close Interval Potential Survey

Close Interval Potential Survey (CIPS) is a survey technique that provides a
detailed continuous pipe to soil potential profile. In normal operation, Pipe to
Soil Potentials measured only at test points. When measuring a potential at
one location (test point), the amount of pipe sampled in the measurement is
considered the length of the pipe encompassed by a 120° arc entered on the
reference electrode. To determine the potential over the entire pipeline
surface require that the reference electrode be moved along the centerline of
the pipe route and place at regular intervals (@ every 2m). The purpose of a
Close interval Potential Survey (CIPS) is to evaluate the criteria of the cathodic
protection, to identify local deficiencies in a cathodic protection system, to
assist in identifying the causes of such deficiencies, and to aid in determining
the requirements to enhance the level of cathodic protection to the structure.

 Assess adequacy of Cathodic Protection System
 Stray Current identification
 Above ground survey
 Able to detect interference from   foreign structure
 Pipe-to-soil potential readings between test station does not accurately reflect the pipe                potential between test station.
 CIPS takes potential readings at interval of 2 meters.
 There are measurement error when taking potential with current flowing, known as IR error.
 To overcome IR error, TRs are interrupted using GPS Current
    Interrupter, true pipeline potential are taken when current stops flowing