Application considerations for high resistance ground retrofits in pulp and paper mills

Safety and reliability of low voltage-high resistance grounding (HRG) schemes have made them an excellent choice for application in the pulp and paper and other process industries. As facilities shift toward this technology for low voltage substations for improved reliability, retrofitting existing grounded systems requires several critical application considerations. This paper briefly reviews different grounding methods and their theory of operation. Then, examples of actual installations are presented that will identify potential misapplications of high resistance ground retrofits, discuss what typical ground voltages and currents to expect, and present important considerations for reliable and safe installation of HRG equipment.