a broader analysis of high-penetration PV circuits than otherwise would have been possible. Thanks are due to Southern California Edison (SCE) for their long-term support of the project and for providing circuit models, operational data, and access to real-world sets of distribution systems on which the findings of the project are summarized in this handbook. The information included in this handbook, and the general scope of the handbook, was steered and edited by a select number of distribution engineering experts formally organized into the Distribution Energineering Review Committee (DERC).

This study presents first results from a pilot project on using fault indicators and self-healing in medium-voltage distribution grids. Directional earth-fault indicators were chosen and deployed in real environments to test their functionalities and quantify their benefits for efficient grid operations. Self-healing concepts using these indicators will be tested in the described project. Different communication schemes will be explored in order to find the most costeffective solutions. Theoretical potentials of the expected benefits of the fault indicators located at different positions in the grid were modelled and will be compared to the results from field tests.