At Intermountain Rural Electric Association’s request, NEI developed and implemented the protection / sectionalizing philosophy for the 115 kV transmission line segments between Castle Rock and Smoky Hill.  The approach was multi-staged, encompassing existing conditions, future substation construction, and the implementation of high-speed optical communications.  As part of the work, NEI reviewed the existing protection scheme for the 115 kV line segments already in place.  Settings were collected from the existing relays and Xcel Energy and NEI modeled the system.  NEI quickly discovered the relay settings were incorrect and some relay algorithms had been misapplied, placing many of IREA's customers at risk for an outage for a single fault.  NEI immediately developed new settings, placed them in the relays, and performed testing to ensure the greatest amount of security was balanced with the appropriate level of reliability.  Soon after the initial work was complete, a drill rig initiated a permanent ground fault.  The scheme developed by NEI worked correctly.  Had the old settings been in place, multiple distribution substations would have been shut down.

IREA was getting false tripping on its Roberts Tunnel Substation and this was adversely affecting the Denver Water Board's Robert's Tunnel Hydro Generation Station. NEI determined the problem to be an incorrect protection scheme, field corrected the problem and eliminated the false tripping. 

EI provided technical assistance and court testimony in a law suit filed against IREA for electromagnetic Fields from a 115 kV transmission line. 

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