RURAL ELECTRIC COOPERATIVES IN THE 21ST CENTURY
Breakers & Switches
by Bill Kornrich, Powell Valley Electric Cooperative Member Voices
I recently spent a day with Travis Tolliver, PVEC Director of Apparatus Maintenance. We drove through areas covered by the Sneedville and Jonesville offices, checking the five substations in Virginia and two in Hancock County. Each substation is inspected on a monthly basis to make certain that there are no problems or issues that will interfere with the work of the substations to transmit electricity to PVEC members.
Although computerized systems do most of the work of monitoring and maintaining the electricity network, regular in person inspections are essential. Maybe mice or rats are sneaking in where they do not belong, or birds are building nests up in corners of steel structures of the substation, or water has been blown into buildings during storms, Visual inspection and on-site checking of gauges and monitors are needed to insure that power moves smoothly along the 3,500 miles of distribution and transmission lines.
A good bit of what I was told was new to me, and I don’t think I grasped all the technical terms involved. However, the day made me appreciate how much planning, thought, and work goes into the operation of PVEC’s power grid. PVEC has well-trained linemen who have a difficult and dangerous job keeping our power on. Thank them any time you have a chance.
Last week, the power blinked several times in our house – meaning that clocks had to be reset and the desktop computer restarted. This was aggravating, and I remember grumbling about it..
Turns out this “blinking” activity means that the breaker, one important part of the system, is doing its job.
There are single phase and three phase breakers along the power lines. These work like a circuit breaker in your house. However, these breakers automatically give four chances to the line to come back into service, attempting to reset the affected area each time. So, when you get four blinks, the system is trying to reactivate itself.
Some parts of the system have fuses, rather than breakers. If damage is done to a line that is controlled by a fuse, then the fuse must be replaced when the damage is repaired. When the fuse goes, there is a loud boom that sounds something like a shotgun.
I also learned about “backfeed”. The system is designed to send electricity in one direction. However, the use of switches on the line allows electricity to flow in the opposite direction or “backfeed” in case of an outage.
Computers at Cooperative offices assist linemen in locating the problem area, and a crew goes to repair it. In order to work safely on the problem, a switch is flipped open to stop the electricity flow before the problem spot. Then, by flipping open a switch after the problem spot, power can flow in the opposite direction from another substation or line feed. This backfeed provides electricity to everyone else after the switch until the problem is repaired. This is called “backfeed”, since power is fed from what is ordinarily a backwards direction.
We tend to take electricity for granted. We rely on it for so much. Using switches, breakers and fuses are ways that PVEC works to keep electricity flowing to as many homes as possible during an outage.
Everyone needs to learn more about our electric cooperative. For more information, go to pvecmembervoices.wordpress.com