| CPC H04B 10/07955 (2013.01) [G08B 21/182 (2013.01)] | 14 Claims | 

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               1. An intelligent electronic device (IED) to monitor an electric power system, comprising: 
            a receiving subsystem to receive an optical signal encoding data comprising at least one parameter of the electric power system after the optical signal passes through a plurality of optical connectors distributed in the electric power system; 
                an optical power monitoring subsystem to: 
                measure a power of the optical signal at the receiving subsystem during data receiving operations; 
                  compare the power of the optical signal to a minimum power threshold value; and 
                  determine when the power of the optical signal is below the minimum power threshold value at least partially due to dissipation of optical energy from the plurality of optical connectors distributed in an electric substation of the electric power system; and 
                an alarm subsystem to: 
              generate an alarm when the optical signal is below the minimum power threshold value. 
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