Nashville Electric Service, Nashville, TN

Introduction:
It was a storm utility personnel and emergency managers have nightmares about. A huge snowstorm hit Nashville, Tennessee on January 16th, 2003, forcing the city to shut down within minutes of the first flakes. It took 4 hours to drive a typical 15-minute drive. Nashville, Tennessee, which received no snow in the entire 2001-2002 season, was not prepared for snow, let alone 7 inches of heavy snow in a very short time. It was Nashville's fifth-greatest daily snowfall on record.

During the Storm:
Needless to say, public communication systems were challenged by the event. Cell phones in particular were bordering on useless as emergency crews and stranded residents flooded the cell phone network with calls. Busy signals and dropped calls were the norm and not the exception. In cases where connections were successful, it often took many minutes just to place a call.

While this all was unfolding, Walt Brostrom, a Senior Engineer for Nashville Electric Service, wondered how his Telemetric communications system would perform during the emergency. Since the system uses the control channel of the cellular phone network, Walt was more than a little worried the system would experience severe communication problems.

Based on his experiences, Walt is happy to report, that everything worked just fine. Walt placed a total of 30 calls to his devices in the field and received 29 responses back promptly. And what about the 1 missing call? That device had reported a power outage and gone to sleep, just as it was supposed to do, in order to preserve its battery. Of the other 29 calls, just one device had to “retry”, just one time, in order to get through. Since the Telemetric devices will retry up to 5 times, for a total of 6 calls, there was still plenty of opportunity for the device to get through.

About Nashville Electric Service:
Nashville Electric Service is among the twelve largest public electric utilities in the nation, distributing energy to more than 328,000 customers in Middle Tennessee. The NES service area covers 700 square miles, all of Davidson County and portions of the six surrounding counties.

Nashville’s Application:
Nashville has deployed Telemetric’s TC012 capacitor bank monitor and switch control at 50 locations throughout their 700 square mile service territory. Nashville uses the Telemetric TC012 to detect capacitor bank problems including stuck switches, blown fuses, and failed capacitor banks by monitoring the capacitor bank neutral current. All this adds up to big savings as Nashville is able to avoid labor costs and improve their power factor with one low cost device.

Future Plans:
After completing their initial installation and study of the Telemetric technology for monitoring and controlling capacitor banks, NES plans to use this same technology for other distribution automation applications. Telemetric offers solutions for the automation of capacitor banks, switches, regulators, reclosers and fault detectors, as well as remote voltage monitoring.

How the Telemetric System Works:
The Telemetric MicroRTU communicates wirelessly over the cellular phone system’s digital control channel. The control channel offers many significant benefits including two-way communications, low monthly fees, significant coverage throughout North America (98% of population), and a robust and reliable communication mechanism. These factors greatly reduce the barriers to expanding automation. Telemetric integrates this communication method into a usable application for down line automation. For more information, please see communications_overview.pdf.

About Telemetric:
Telemetric is the industry leader in low-cost wireless solutions, providing utilities with an affordable option for communicating with down-line equipment and machinery. Telemetric has helped over 100 electric utilities with their automation needs. For more information, please visit www.telemetric.net, or send e-mail to info@telemetric.net.