Consistent inspection and assessment of T&D assets by field personnel can be challenging. Some cases present conditions that have never been seen before; other times, different inspectors assign different ratings or actions to the same condition. Understanding the root cause of the condition and the possible resulting failure mode can improve the quality of inspections.
The EPRI team has been investigating the degradation and failure of T&D assets for decades. These investigations have included evaluating units removed from the field and laboratory testing. In addition, EPRI-member utilities have submitted many images, thus building the industry’s knowledge base for addressing aging assets. In 1998, EPRI assembled its first T&D field guide for the inspection and assessment of composite insulators (also called polymer or non-ceramic insulators). This guide was a success, with members observing better field inspections and communication between utility subject matter experts and field personnel.
Because of that success, EPRI started developing field guides for many other types of assets, including foundations, structures, conductors, and so on. Next, the scope of the series expanded to cover technologies, such as infrared and daytime corona inspection and grounding measurements. Twenty-six field guides have been developed to date.
Progress, Results & Next Steps
The first field guides were available in print only, in a large, 8.5×11 format. Soon, though, a more compact product better suited for the field was introduced. Responding to the needs of utilities that were bringing mobile computing to their field personnel, EPRI then migrated the guides to electronic PDFs, which enabled videos to be imbedded.
As mobile phones with advanced operating systems have become more ubiquitous, EPRI has developed iOS and Android apps. The apps allow much more flexibility — such as by enabling utilities to implement their own ranking system or using the “pinch” function to zoom in on an image.
Looking ahead, artificial intelligence could make it possible for users to photograph a composite insulator, feed the photo to an app, and learn from the app when and by what manufacturer the insulator was made. New developments are underway.
How to Use the Research
T&D utilities can use the EPRI field guide series with their field personnel to improve the consistency of inspections. The guides are also a great way for early-career personnel to become exposed to the conditions that occur in the field and to learn those conditions’ impact on reliability.
How to Get Involved
The iOS and Android apps can be downloaded from the Apple or Google Play stores, and eligible members can access the field guides using their EPRI login. PDF versions of the field guides are also available from www.epri.com; some are available to the public. PDFs of the field guides are available to North American Transmission Forum members on the NATF website.
As T&D companies identify new assets and conditions that need field guides, they should work with the EPRI team by submitting images and guiding EPRI in the development of new guides.