Deliverables on Underground Assets

Summary of past deliverables related to distribution underground assets

Recent deliverables on distribution underground assets.


Distribution Underground Switches: 2021

This is a multiyear project investigating the life cycle of underground switches. The 2021 research included examination of a field aged, gas insulated submersible switch and development of an outline for a guidebook planned for 2022.

Findings from this work can be used to inform your material specifications, inspection and diagnostic approaches, and maintenance to achieve better performance in your switch fleet.

MV Cable Accessory Research: 2021

This is a multiyear project investigating the performance of medium voltage (MV) cable accessories. The 2021 research included the performance of forensic investigations of various accessories as well as continued longer-term research to understand and illustrate the impact of various workmanship approaches on the anticipated health of MV cable terminations as determined by the presence of partial discharge (PD). In addition, 2021 research included investigation of online PD diagnostic techniques.

Findings from this work can be used to inform your material specifications, inspection and diagnostic approaches, maintenance, and craft practices associated with accessory preparation to achieve better performance and improved reliability.

Low Voltage Cable Accessory Research: 2021 Update

This is a multiyear project investigating the performance of low voltage (LV) cable accessories. The 2021 research included forensic analysis of aged and failed LV connectors, analysis of various crimp methods, and materials analysis of LV cable components subjected to heating in the laboratory. The research also included analysis of data collected from the long-term testing facility at EPRI’s Lenox Laboratory.

This research is aimed at producing information to better understand the implications of design and preparation practices on connector performance and life, and to inform infrared thermography.

Infrared Thermography in MV Underground: 2021

This research included a survey into practices and challenges associated with the use of infrared thermography on UG distribution systems. In addition, the research included analysis of IR results from laboratory research into low voltage connector heating.

This research aims to explore industry practices and approaches to mitigating the challenges of acquiring and, more importantly, interpreting IR imagery.

Dissolved Gas Analysis for Network Transformers: 2020 Remote Sensor Evaluation

This research focused on testing of a remote DGA monitor for use on network transformers, including submergence testing.

Results from the research will inform the remote gas monitor selection.

Risk Mitigation of Manhole Events: 2021 Update

This is a multiyear research project investigating risk mitigation of manhole events, including testing to understand gas produced when LV cables overheat and arc, and evaluations of technologies to identify precursor issues. 2021 research included study of EPR cable materials exposed to arcing.

Results from this research will inform sensing technologies for early identification of conditions which could lead to manhole events, as well as remote manhole monitor selection, deployment, and settings.

Bronze Book: 2021 Update

The Bronze Book is a reference aimed at utility engineers and personnel involved in the planning, design, manufacture, installation, operation, and maintenance of underground distribution systems. For 2021, EPRI added content on Cable Testing and Diagnostics.

Network Training Video_2021

Provides access to a set of training videos, offered through EPRI U, which are part of a comprehensive training curriculum on low voltage network systems.

The training curriculum can serve both new people to network systems, as well as provide enrichment to experienced people.

Low-Voltage Secondary Network Systems Reference

EPRI has produced a comprehensive, stand-alone reference on network systems. It includes content on network components and their operation, network designs, protection, modeling, arc flash reduction, and distributed generation on network systems. Book to be issued in early 2022.

Underground Practices Repository_2021

Provides access to an online repository of underground practices to facilitate comparisons and aid decision-makers in identifying practices in place at other utilities that can be applied to their utility to improve performance.

Last modified January 28, 2022