By Tom DeWitte and Tom Coolidge
Have you ever spent a day in the field with a senior cathodic protection (CP) field technician? It is an eye-opening experience to hear and see firsthand the struggles and difficulty they face maintaining a pipe system’s CP system. If you have not and are involved in any way with managing CP data, we strongly recommend it.
Spending time in the field with a CP technician will expose you to numerous test point readings, rectifier inspections, and other maintenance activities. And if you are lucky, you will get to see what happens when a test point reports an unacceptably low reading. When this happens the entire CP circuit is considered to be “down”. This begins a troubleshooting process that can literally take months to resolve. Yes, that is not a typo, it can take over a month for a senior technician to locate and resolve the root cause of a low test point reading. A part of the reason for this long duration is access to information and tools to understand the circuit. A modern GIS utility system can be a key provider of this information and tools. Here are a few examples.
A common question a CP field technician will ask when trying to understand the circuit they are inspecting is “what is the extent of this circuit”. This is where the Esri Utility and Pipeline Data Model (UPDM) and its pipe-specific configuration can help. UPDM provides a configuration of the properties and capabilities of ArcGIS and its utility network to help address this question.
Within UPDM is a configuration for managing CP assets. This includes a subnetwork configuration that when utilized will generate and maintain a graphical representation of each unique CP circuit. This subnetwork layer is a standard Geodatabase featureclass that can be displayed in web and mobile applications. This means field technicians can view this information in the field on their mobile phones, tablets, and laptops.
When a CP field technician receives a test point reading of less than -0.85 Volts, the circuit is considered to be “down”. The next step for the CP field technician is to find and test the other test points on the circuit to see if the deficient reading is an anomaly.
CP circuits are not always simply the connected metallic pipe assets running down a street in a straight line. Sometimes they are spidery meandering subsystems whose legs stretch in many directions. This can make it difficult to locate the other test points associated with a specific CP circuit.
Finding those other test points is a simple subnetwork controller trace with the ArcGIS utility network tracing tools.
With the circuit’s test points now identified, the technician can easily locate and test the other test points.
When trying to locate the root cause of a CP circuit’s low reading, the field technician may decide to install an insulator to split the circuit. Here is another example of where the standard tracing tools provided with the ArcGIS utility network can help.
Adding an insulator is a simple attribute update with the UPDM configuration for CP. All the editor needs to do is to update the fitting or device “Bonded/Insulated” attribute from “Bonded” to “Insulated”. The embedded attribute rule will automatically update the “Cathodic Protection Traceability” attribute to “Not Traceable”. Cathodic Protection Traceability is configured to be a utility network, network attribute as part of UPDM. This allows the attribute to be used as a constraint value by the standard ArcGIS utility network trace tool.
Rerunning the same CP connected trace, shows the new configuration of the cathodic protection.
With this new trace result a CP field technician can see the results of what the extent of the CP circuit will be with the newly installed insulator.
These examples of analytics and visualization of analytical processes can provide CP field technicians with the information and tools they need. Having this information and these tools can help CP departments to improve this time-consuming and expensive process.
If you are someone who supports or assists with CP management at your organization, get your steel-toed boots out of the back of the closet and spend a day in the field. The understanding and appreciation of what these professionals do and their struggles for information and tools will be impactful.
If you missed our previous blog articles on Managing Cathodic Protection with UPDM, here are the links to those articles. In early 2020 we wrote a series of blog articles about leveraging the capabilities of ArcGIS to address the data management needs of cathodic protection for pipe systems. Those three blog articles explained how to organize and maintain information about a pipe system’s cathodic protection system.
PLEASE NOTE: The postings on this site are our own and don’t necessarily represent Esri’s position, strategies, or opinions.
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