SCADA Applications & Installations:
NCPA's Communications Solution
The Northern California Power Agency, Hydroelectric Project near Murphys, California has a main generation capacity of over 245 MW. The project has three smaller units at a remote location and overall covers a geographical area of approximately 40 miles of mountains and canyons. Included are five diversion dams, two feeder streams, a tunnel, and a main penstock with a total head of over 2,000 feet. Data for all stream gauges, lake levels, fish flows, and penstock pressures utilize many Control Microsystems' TeleSAFE Micro16 SCADA Controllers via two VHF telemetry links over a microwave backbone.
Having only one keying channel and two VHF data channels, a TeleSAFE model 6000-16EX is used to serve as a SCADA controller for both keying radios and providing data control by using the store and forward feature to route the appropriate data to either the upper and/or lower project areas as needed.
A Micro16 has total automatic control over remote fish flow valves by simply sending a set point. Preliminary experiments have proven the feasibility of using automatic fail-over distributed control in the event of primary communication failure. This is accomplished by using the second port on the TeleSAFE Micro16 SCADA controller and expanded memory for the additional Ladder Logic Diagram programming. Fail-over communication between the RTU sites is achieved by using spread spectrum radio links with a store and forward unit as a repeater. If it sounds tricky, it is.
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Trademark Acknowledgments: TeleSAFE, Micro16, SCADAPack, and TelePACE are trademarks of Control Microsystems.
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