04972290 is referenced by 48 patents and cites 3 patents.

Monitoring and control of analog electromechanical protective relays and digital mcroprocessor based relays is integrated through a system including slave stations which record and time tag contact activity at each of the analog relays. The slave stations continuously retain digital samples of a predetermined number of the most recent cycles of the currents and voltages at the analog relays and when a trip occurs store the retained samples as pre-fault values together with a preset number of post-fault samples. A master station communicates with the slave stations monitoring the analog relays and with the digital relays through a two way communications network. The master station repetitively polls the slave stations and digital relays for contact activity. Detailed data such as the time tags and pre-fault and post-fault currents and voltages are then requested from those stations reporting contact activity. Either the slave stations or master station calculate fault location and type from the fault voltages and currents, an periodically calculate routine metering parameter such as watts and VARs.

Title
Electric power system with remote monitoring and control of protective relays
Application Number
7/414975
Publication Number
4972290
Application Date
September 29, 1989
Publication Date
November 20, 1990
Inventor
James P Garitty
Coral Springs
FL, US
John S Wargo
Coral Springs
FL, US
Shan C Sun
Coral Springs
FL, US
Agent
Richard V Westerhoff
Assignee
ABB Power T & D Company
PA, US
IPC
H02H 3/18
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