PREMS II (Portable Radiated Emissions Measurement System) is an advanced, portable diagnostic tool developed by EPRI to detect and locate sources of electromagnetic interference (EMI) and radio frequency interference (RFI) that can cause power quality issues in utility distribution systems and customer environments. The system is designed to be easily deployed in the field—typically mounted in a utility service vehicle—and remotely operated via a web interface on a laptop, tablet, or smartphone. It integrates GPS for precise mapping and can export measurement data for visualization in GIS platforms, enabling utilities to pinpoint problem areas on their grid networks.