Measurement of Instant off Potential of Steel Pipelines in Conjunct Urban Gas Distribution Networks

Measuring the instant off potential of pipelines in order to specify the cathodic protection condition of the pipelines and provide an overview of the quality of the coating is inevitable. However, there are many challenges in measuring this quantity for urban gas distribution networks due to interconnected structure, current interferences, especially interferences of local station networks, connection of new and old networks with different required potential levels, existence of networks with Different coatings in one area, worn urban structures, traffic and number of test points, large number of stations in the target area, have been identified. In this paper, an attempt has been made to provide solutions to the above-mentioned challenges resulting from IOP measurement experiences in the Ahwaz metropolitan gas distribution network and the requirements that facilitate project implementation, as well as data collection with higher accuracy. The measurement was based on the use of interrupter and fast data logger synchronizable that could be connected to pc. However, the contents can be generalized when using other equipment, such as trans-rectifier timers and usual voltmeters (in accordance with the instructions for use).