Today’s LiveWire Spotlight evaluates three “teachable moments” posted by NERC where the need to revalidate routine assumptions became clear after an electric system event took place.

  1. A thin patina of dry salt on insulator columns supporting four disconnect switches caused flashovers during a rain shower.
  2. Although all four ground Faults directly induced by the flashovers properly cleared, an unusual series of relay Misoperations occurred in the adjacent systems.
  3. Discrepancies between the product development, quality assurance, and production EMS led to SCADA losses in two separate incidents.

The need to revalidate routine assumptions appears as a corrective action in almost every BES service loss.  Severe penalties may be levied if an outage occurs, and it is found that an Owner or Operator did not act upon these Lessons Learned.