E-REDES : a new model, based on EN 50522, to manage earthing systems in secondary substations

Portuguese Regulation regarding the Safety for Substations and Secondary Substations (SS) states the obligation to measure it s earthing resistance, being this the only criterion for evaluating people's safety in these facilities. E-REDES, the Portuguese Distribution System Operator (DSO), manages Secondary Substations and their earthing systems. Efforts were made to change the Regulation, and, among other procedures, it was defined that alternative methods can be established for SS by applying th e measurement methodology specified in EN 50522. Therefore, to implement this new approach, a multidisciplinary Working Group (WG) was created, and one of the outputs is a practical guide. This paper focuses on how E-REDES implemented this new methodology and established a new standard procedure describing all the rules and necessary steps to fulfil regulatory demands.