The days are lengthening and daffodils are only a month away, but this challenge remembers another winter when thick sheets of sleet enveloped the ground and wipers froze to windows. It was a brutal winter offering only an occasional glimpse of the sun. It was the Yukon.
Even when the snow stopped falling there was no relief. A cold wind continued to bend the maples and oaks, rattling their branches, and, unable to knock the white stuff from those branches, moaned to us through leaky windows. The dog couldn’t stand outside long (then again she was a city creature
with a physique fit for a couch, not a snow bank).
During the dead of that winter, we traveled to the Northern Territories in western Canada, chasing the late afternoon sun as we flew from DC to Seattle and then hopped the border northward to Vancouver. In Vancouver we met our hosts, three local engineers — Tyler, Terry and Bill — who would accompany us north. After perfunctory introductions (one doesn’t dawdle on a Canadian tarmac in January), we bundled bags and bodies into an eight-seat puddle jumper. After one more short flight, we set down in a stiff crosswind onto the single runway at Prince George, an outpost town on the Trans-Canada/Yellowhead Highway.
“The rental car will be parked at the terminal,” the agent on the phone told me a few days before. “The keys are on the visor and the contract on the dash. Just fill it with gas when you’re done and I’ll send you a bill.” Those were, indeed, different days, and it was a different place.
We exited the double-wide trailer-sized terminal, tended by a bored gate agent turning the pages of the local paper for the fourth time that day. In the lot, the cars all had electric cords lolling out the front of their grills because, if you didn’t plug in the crankcase heaters overnight when the mercury retreats to minus 30o, the oil around the crankshaft turned to honey-thick sludge that no starter could turn.
Tyler unplugged the sedan as we piled in. The hesitant V8 groaned, then sputtered to life, and we headed to the only hotel in town. Along the way, one of the veterans directed us to a quick pit stop; the local ABC retailer, where we loaded up on our own individual form of anti-freeze.
“The winter nights are kinda long out here,” Terry laughed, “and cold.”
“Ya, ya. And za men come out of woods in Spring to shower,” Bill replied in a mock-Russian accent. Picking up his brown bag with a liter of Stoli from the counter, he added, “Let’s go.”
Our companions worked with the field engineering group at Westcoast Transmission, based out of Vancouver. Founded in 1949 by the late Frank McMahon, Westcoast provided a few billion cubic feet of natural gas per day to the United States and the eastern cities of Canada. The pipeline, called the Big Inch, pushed the gaseous gold between remote pumping stations throughout the territory to energy-hungry consumers. The stations were spaced at intervals of a few hours drive along the pipeline. Our task was to take some measurements and look at a noise problem at one of the stations. (The “big inch” referred to pipes that were 20 to 48 inches in diameter. In the larger branches, a man could crouch and walk through the line.)
Two kinds of pumping stations were operated along the Big Inch: the first type were installed in the late 60s and the others came on line during the 80s.
Our first stop, the lower quad station, was of the older variety. The pumps were powered by four-stroke V-12 engines, not your Jaguar sports-car variety — but freighter-sized boat motors adapted for the job. These machines were as large as a two-bedroom home, with cylinders large enough for a man to squeeze into.
The beasts ate the same stuff they were pumping, with one-inch copper tubing feeding the natural gas to injectors at the piston heads. To reach the spark plugs (two serving each piston) a technician needed to climb a 20-foot ladder.
The pump house contained ten of these behemoths lined up in a row on a concrete deck. The room shook as the monster machines rumbled and grumbled, and the deck vibrated enough to induce minor vertigo. We made some measurements and shrugged our shoulders. Everything here was working fine.
The next pump station, four hours away, was one of the newer ones served by jet turbines instead of the mammoth V-12s. (If memory serves, the boat engines cranked out about 10,000 horsepower, and the jet turbines roared with 100,000 HP). But the afternoon sun, which had risen only a few degrees above the horizon, was retreating quickly, so we beat feet back to the hotel as the sun dove into the snowy plain. With not much else to do, we shot pool and watched championship curling on the tube in the bar.
The following morning we set out north, driving over the flat lands and into near-virgin forest. We were the only car on the road in either direction as we headed to this second pumping station.
Arriving at the earth-bound jet with an uber-sonic scream that pierced ear plugs and ear muffs, we set up our antennas and spectrum analyzer to map the space, collect some data and perform quick checks of the control instrumentation. After a cross-continental trip and two days buzzing around the Yukon in dire winter, we were beginning to wonder what the heck we were doing here.
Outside, we packed up our gear and asked, “Where’s the problem?”
Tyler shouted back over the whine of the machine, which was still cutting through at 90 dB although we were sitting in the car parked outside the building. “No problems here! This is just to have a look. But we’ve got some kind of noise at the next pumping station. We’ve got the big V-12s there.”
He turned the car around in the parking lot and we headed away from the scream. “You’ll see. The control feedback loop signals are bouncing all over the place. We just installed the same new systems in two places. One works great, but the other has lots of noise and jitter.”
“Remember the lower station?” Bill asked. “You know, the first place…yesterday afternoon?”
“Well, this next station is exactly the same as that one: same layout, same engines, same control, same everything — or it’s supposed to be.”
We drove while Bill and Terry traded jibes over last night’s curling match. “You owe me five loonies, Bill. Saskatoon’s number one. Again.”
“I’ll pay ya in beer when we get back,” Terry laughed.
By mid-afternoon we arrived at the third location. Indeed, it was the same building; a large weather-beaten steel-paneled building, loudly thrumming. “Let’s go inside.”
Engine 3 was down and a mechanic was crouching inside the crankcase. We looked over and his head popped up from the cylinder casing. Wrenches, two feet long, were laid out on the ground. I kicked one. It didn’t move. Terry waved at the mechanic, who was wrestling with an enormous thrust-rod nut.
“Take a look over here,” Terry motioned us to the wiring that fired the dual spark plugs sprouting from the enormous heads. Not much different from a ginormous lawn mower engine. The wiring was tied to the natural gas supply lines that fed injectors on the heads. Then all were tied neatly back to an enormous distributor. Gray sensor cables were wrapped on the same array.
We asked to see the sensor collection point. The shielded twisted pairs that carried sensor data were pulled neatly into the breakout box, the same as at the first station.
“But look at the shields,” Norm said. We all looked down. There was the problem. “Two different guys wired these systems.”
What did Norm see?
Excerpted and adapted from the IEEE EMC Society Newsletter, Winter 2011. Used by permission.
|Mike Violette is President of Washington Labs and Director of American Certification Body (firstname.lastname@example.org). Mike is just beginning to thaw out from his trip to the frozen North.|