Synchrophasor technologies can monitor electrical conditions across regional transmission grids and deliver that information to operators and reliability coordinators. Deployment of these technologies is revolutionary for two reasons. First, phasor measurement units (PMUs) record power system data 30-to-120 times per second, which is more than 100 times faster than current technologies. Second, each PMU time-stamps every measurement it takes, enabling all data to be synchronized across large regions of the country. This data can be used to create in-depth “pictures” of operating conditions on the grid and enable operators to detect disturbances that would have been impossible to see in the past. Some experts have compared synchrophasor technologies to “MRIs” for the transmission system because of the detailed operational pictures they can provide. Synchrophasor data are being used for forensic analysis of grid disturbances, because the detailed, time-synchronized data allow investigators to immediately understand grid conditions before, during, and after the event and diagnose its causes.