Instant off or on-off interrupted potential survey is a close interval survey (CIS) method used to determine if corrosion is taking place and to what level on a pipeline. GPS synchronized interrupters to control all current sources and interrupt them simultaneously. Interrupters can be set for any predetermined length of time. When the close interval survey (CIS) crew is taking data, readings are done when the cathodic protection system is on and when the cathodic protection system is in an “instant off,” or polarized potential condition.
If the cathodic protection system current source cannot be interrupted, the on potential survey method may be used.
MATCOR Interrupted Potential Surveys
Qualified MATCOR technical personnel can conduct instant on or on-off interrupted potential surveys in the field for oil, gas and water pipelines. Data is then analyzed by NACE certified experts.
With MATCOR, you benefit from:
- Over 45 years of experience with all types of cathodic protection systems
- Experience testing, installing and maintaining cathodic protection systems for all types of structures throughout the world
- Highly qualified professional and NACE corrosion engineers and technicians
- Team members with experience on the client side of CP projects
- Experience managing multi-million dollar CP projects and corrosion departments of large utilities and pipeline companies
- MATCOR’s many proprietary cathodic protection systems that are lower in cost and have longer lives than some commonly used CP systems
MATCOR’s mission is to solve your corrosion problems. We are ready to assist with your corrosion engineering and field service needs, including design, manufacturing, installation, commissioning and ongoing maintenance, as well as project management and full turnkey solutions. In addition, we offer a broad range of proprietary corrosion prevention products.
To get in touch with our team of corrosion experts for more information, to ask a question or get a quote, please click below. We will respond by phone or email within 24 hours. For immediate assistance, please call +1-215-348-2974.Contact a Corrosion Expert
4 thoughts on “Interrupted Potential Survey”
i just want to know everything about on-off potential. because when we interrupt cp panel than why on potential go more than high limit of 1.20. and another way when cp unit is normal that time it is related to on potential.
Dear Mr. Kapil Jangid,
Thank you for your web comment. We will have one of our engineers reach out to you via email to get a better understanding of your question.
How long can you continuously interrupt a system to complete and survey? hrs, days?
Thank you for your response to our posting. We apologize for the long delay in getting back to you. We recommend that the interruption only occur for the period of time required to complete the survey in that area. However, the interruption has minimal impact on the corrosion risk associated with the pipelines being interrupted because the interruption cycle does not lead to depolarization of the protected pipelines but merely stops the flow of current to allow for a potential reading with no IR present as the I (current) is momentarily interrupted and dropped to zero. Even during the OFF cycle, the pipeline remains polarized as depolarization takes much more time than the brief milliseconds of current interruption.
We hope this helps!