Southern California Edison (SCE) is installing limiters covering hundreds of miles of power lines as part of the company’s broader wildfire mitigation strategy.

SCE’s Rapid Earth Fault Current Limiters detect and rapidly reduce the voltage on downed power lines—also known as conductor—to help prevent them from sparking fires or becoming public safety hazards. The equipment also reroutes power to compensate for downed lines, mitigating the risk of customer outages.

“At the first sign of trouble, it redirects voltage away from the impacted conductor. It can operate without blinking lights or customer turnoffs,” said Jesse Rorabaugh, a senior engineer at SCE helping to install the new equipment. “This technology is an example of SCE trying to get to the point that even when bad things happen, the power lines aren’t releasing enough energy to cause ignitions.”

SCE has installed these devices on a circuit in the west end of the Antelope Valley, near Gorman, Calif., and in parts of Los Angeles and San Bernardino Counties. By the end of 2023, SCE expects to have the equipment installed on three substations covering 847 miles of circuitry, of which 373 miles are in areas at high risk for fires.

The Rapid Earth Fault Current Limiters are the latest SCE initiative to help prevent wildfires. The company also has installed cover conductor, improved vegetation management, and started undergrounding power lines in certain high-risk areas. Because of these initiatives, there has been a 75-80 percent reduction in the probability of catastrophic wildfires associated with SCE’s equipment since 2018.