Power shortages caused by programming glitch

“It was seeing double the current that was actually there,” he said.

The piece of equipment serves as a giant circuit breaker effectively, and once it turns power off, it is programmed to turn power back on after a set period, which is why the power kept coming back on, according to Titus.

The first outage was at 4 p.m. and the last at 6:12 p.m.

Triggering the problem was the warmer weather on Sunday. Crews made a temporary fix to the problem early Sunday, and were doing permanent repairs Monday morning.

Customer calls let them know it was happening frequently, he said.

Titus said he had never before seen the power go out so many times. People took to Facebook to ask if anyone else was experiencing power outages, and in comments kept a running tally of how many times it had gone out.

He said if the problem had happened during normal working hours, “we would’ve been there in a quicker period of time.”

The circuit breaker is designed to turn interrupted power flow back on. ‘It was tripping on overcurrent and tripping back after the appropriate time that was programmed in there,” which was three minutes, he said.

It is programmed to fix itself and that’s what it was trying to do, but then it came across misprogrammed information telling it it needed to shut down, he said.

This particular piece of equipment was installed a few years ago, said roger Kline, PUD general manager. Crews are also checking other areas to ensure the same programming issue is not present elsewhere.

Kline added, “Some circuit protection devices require line inspection and human intervention prior to resetting. As this one is not typically dangerous to life or property it is allowed to reset and reclose [allowing power to flow again]. Eventually, a counter would have held the device in the tripped state until human intervention could investigate and remedy the root cause.”