Published March 26, 2006 ~ By David F. Ashton
In an effort to isolate the problem, a PGE engineer opens a massive switch at the Johnson Creek Substation just as a power serge comes through the system. The result is this massive arc. No one was injured. Photo by David F. Ashton
¬†Standing outside the fence at the massive Portland General Electric (PGE) electric power sub-station on SE Johnson Creek Blvd., at Flavel Drive., one can hear a loud, deep, resonant hum as the giant electric transformers pass electricity to homes and businesses throughout East Portland.
Throughout the afternoon of March 19, there was a quite different sound. Every few minutes, a low toned, resounding “thuang” noise growls from the power station transformers. “That‚Äôs the sound of a ‚Äòhit‚Äô somewhere in the system,” a PGE worker, who asked not to be identified by name, tells us. He says this means something, somewhere is shorting out Portland‚Äôs east side main, high-voltage power system.
A PGE Crew members uses test equipment, trying to locate the problem on the power grid that shut down Precision Cast Parts on March 19. Photo by David F. Ashton
In homes and businesses, from inner SE Portland to western Gresham, this “power anomaly” — as the electrical works describe it ‚Äì happens repeatedly, from early afternoon through the early evening hours. The lighting go brown, appliances groan to a stop, then the power goes completely out for a few minutes.
These repeated blackouts, followed by a power surge as the juice came back resulted in blown surge-protectors, but no real damage, at our home office. Because it is a Sunday afternoon, homeowners found the on-off-on power cycle more of an annoyance than anything else.
Cost to Precision Cast Parts: $1 million
We drive the few blocks to the Johnson Creek Substation late in the afternoon to learn more. Shortly after arriving, we meet two men who identify themselves to PGE crew as the Johnson Creek Precision Cast Parts (PCP) Information Technology and Plant Engineering managers.
“Our entire, nationwide computer network is down,” complains the PCP IT manager. “Every time we reset our network, another power glitch shuts us down. We‚Äôre a seven-day-a-week business.” The PGE crew listens sympathetically. But until they isolate the “fault”, they tell the computer manager, they can‚Äôt predict when it will be repaired.
Another “thowang” emanates from the substation. It seems the events are coming more frequently now; each one sounding louder.
“We‚Äôre working to catch up on orders,” says the PCP plant engineer, “and that means we‚Äôre scheduled to turn out as much as $1 million worth of parts today. We‚Äôve had to shut down the plant. This is serious, costly problem.”
Arcs and sparks
“Thowang” ‚Äì again, the power grid takes a “hit”, as the PGE workers call the event.
“We‚Äôve ridden the lines from Sellwood to Gresham and everything looks good,” crackles a report to the two-way radio of a PGE crew member standing near us. “The Midway Substation is OK. So is Sellwood. We‚Äôre looking at the Gresham end.”
A PGE worker disarms the inner electric fence at the power substation. He releases an immense, chest-high lever. The lever is hooked to a thick pipe that travels upward, operating a gigantic power switch located high atop the power station.
At 6:22 p.m., he pulls the switch ‚Äì “thwang” another power hit ‚Äì and the switch contacts arc with a blinding blue light that lasts for at least five seconds. The air crackles loudly as a colossal amount of current jumps from one open switch contact to another. We try to take a photo, but it takes six seconds for our camera to fire up; we catch a shot the final surge, as the switch contacts explode in an orange fireball. Molten metal showers the area, filling the air with a sent of both ozone and an electrical fire. The blast was so loud, it attracted onlookers from blocks around.
The workers are visibly shaken. But they, and the bystanders, are unharmed. “We took inner SE Portland off the grid from this side, just as we took a ‚Äòhit”,” he explains. “But their power is on; they‚Äôre getting electricity from the other end of the grid.” We‚Äôre comforted to learn PGE has built redundant fail-safe systems into our power grid.
Isolating the problem
As the smoke clears, evening is falling. We notice the mighty transformers are now nominally humming. They‚Äôre taking no more hits.
About 6:30 p.m., PGE crews isolate the problem ‚Äì a “jumper” power regulation device at SE 190th Ave. and Powell Blvd., Ariana White, PGE Communications Specialist, tells us. It was failing intermittently throughout the afternoon, she added, but the problem wasn‚Äôt identified until it completely failed.
“While we repaired the jumper power regulator,” White says, “we had to temporarily turn off service to some customers, resulting in phased outages from 6 p.m. to 8:45 p.m. Those without power for periods of time, during the repairs, numbered¬†8,000 to 10,000.”
?ì 2006 David F. Ashton – East PDX News