According to the news on a local radio station this evening the Arizona Electric folks had determined that the reason for the outage was a cascade effect.
IT was caused by one man in one of the 5000 KV relay stations on the line. He was changing out a damaged part, and he touched something he shouldn’t have. That tripped the system off-line. Effecting some 4.1 million customers in Southern Cal and Northern Mexico.
According to the broadcaster I heard they were NOT releasing the responsible man’s name, or indicating they would ‘discipline’ him?
I wouldn’t want to, regardless of whether something went wrong or didn’t.
As noted before I am a retired Electrical Engineer and I have great respect for the workers in our electric power generation and distribution system. Most of them receive this first lesson about the work they are doing: “Your pencil does not have an eraser. Your first mistake will likely be your last.” That pretty much says it.
Again, I observe the similarity to the industry this forum is all about.
…I’ve been reading the previous knowledgeable posts on massive power shutdown with great interest. First, if the person involved that “touched something he should not have”, I’m glad to hear he is alive…Which sounds very surprising.
Thinking about what I’ve just read, it is amazing we maintain our power flow as steady and reliable as it is. Way beyond my comprehension. But I’m certainly glad we have all the intelligence employed where it counts to keep our vast system working for us.
I do wonder how vulnerable our Power Grids might be to those who want to do us harm.
PS: My only experience of being in a “power house” would date back 70 some years ago. It would be in Somerset Co., Pennsylvania at a local coal mine that was generating it’s own power for the mine use and for all the “company houses, company store, etc…”. It was not 60 cy power either. I remember one of the light bulbs from that location would light with less lumens of light in our town, near by served by the regular power company.
What I remember in the “power house” was a massive flywheel turning and one could see just about half of it, as the the other half, was down below that floor level. It was coal fired, steam driven. Not much more memory of it than those several thoughts. But it was awesome to me being just a youngster…with Dad showing me “around”.
That story about the pencil reminds me of another story.
Same plant, except now I was a system operator in the hydro plant down the hill from the diesel plant I referenced before.
We had a 138 kv line trip off due to a broken crossarm about 65-70 miles away. That was OK. These things happen. The cross arm was replaced and the line lifted back into place. Then the fun began. We went to close the line back in and it wouldn’t go. A ground fault relay on the main control board kept tripping out. We tried closing in several times and still no go.
Now that was strange. The superintendent took charge of the situation, not an uncommon thing, and ordered the whole 250 miles of line to be flown and inspected for other faults to ground or broken poles or crossarms, thinking the problem must be somewhere external on the line.
Nothing.
Even stranger.
They (he and the Regional Manager) then called in an electrical engineer from MONENCO, to go over the plant, thinking something must be faulting to ground within the plant, the switchyards or transformer banks. Part of his work entailed inspecting the hydro busses, all three phases of them, along the length of the board in the system control room which was in the hydro plant. I was the day shift operator the day he did this.
My job was to open up the inspection doors on each section of the board for him as he systematically took a megger meter to those heavy copper busses…the whole length of the board, looking for faults in the busses.
Now you know what a megger meter is and how it’s used. The busses of course were energised at something along the order of 7k volts at who knows what number of amps and they were down low.
He got on his knees on a concrete and tile floor and he meggered the works at least 150ft in all. I just kept opening and closing access doors not saying a word as he finished a section and proceeded to the next one. He was a young ma
Charlie - Thanks for that story about the metal shavings in the ground fault relay - another real-life example of “things they don’t teach you in school”. Reminds me of a recollection story in Trains about 30 years ago by a guy who was an EMD locomotive set-up man and instructor, on E-8’s as I recall. The ground relay would trip on right-curves only, and only at certain speeds and super-elevations, etc. After looking in the engine room and electrical cabinet at night with the internal lights out and seeing some flashes, he found a metal flashlight rolling around under the cabinet, which would just barely touch a live terminal lug under those conditions, causing the ground.
I was surprised to see that the Niagara Junction Rwy. electrics lasted into the ConRail era, were included in it, and were even assigned new CR numbers ! Here are links to about 11 photos of them (none mine) of them, most stated to have been taken around 6/30/1977 - see the captions for more details:
Sorry, I was thinking of the Niagara Falls ONT Electric Railway which ran along what is now the Niagara Falls Parkway from south of CNP to somewhere north…around the Rainbow Bridge or even further. It did stop running in the '50’s…
Our family’s trips to the Falls and the Canal rarely, if ever, took us across the line. I’ve not seen or heard of the NJRy. My memories are of the NABISCO plant at the Falls and other such things. We just looked across the gorge…
Sounds like a coal fired steam engine that powered the plant. It was likely 25 Hz which was common 70+ years ago (possibly explaining the lumens difference between their output and