NERC Case Notes: Reliability Standard IRO-003-2


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Midcontinent Independent System Operator, Inc. (MISO), FERC Docket No. NP15-14-000 (December 30, 2014)

Reliability Standard: IRO-003-2

Requirement: R1

Violation Risk Factor: High

Violation Severity Level: High

Region: ReliabilityFirst

Issue: MISO self-reported that its ability to determine projected, potential post-contingent element conditions within its RC was diminished due to incorrect control setting on its Network Model, utilized for alerting operators to System Operating and Interconnection Reliability Operating Limit violations. The problem affected (1) seven transmission lines associated with one station; (2) six tie lines between MISO and PJM Interconnection area; (3) fourteen three-winding transformers; (4) facilities where the Transmission Owner or Transmission Operator (TO or TOP) did not provide a Facility Rating and MISO assigned a default rating; and (5) facilities where voltage monitoring flags were incorrectly activated due to a coding discrepancy in the Network Model update script.

Finding: ReliabilityFirst determined that the violation posed a moderate risk to the BPS reliability as no IROL violations occurred associated with the violations. Furthermore, the only SOL identified by the TOs or TOPs were the ones associated with one substation and one transformer and the TOP worked with MISO to resolve the issue. MISO neither admitted nor denied the violations. In approving the settlement agreement, the NERC BOTCC found that issues related to MISO's Network Model were only associated with the monitoring of post-contingent element conditions and did not hinder MISO's ability to perform other monitoring functions. Moreover, the issues were not related, affected a small percentage of the facilities MISO monitors and were indicative of other technologies that depend on large amounts of data. This was MISO's first violation of the standard and none of the violations posed a serious or substantial threat to BPS reliability. While MISO self-reported the violations, they were delayed. But MISO did have an internal compliance program in place, which ReliabilityFirst considered a mitigating factor. MISO was cooperative throughout the duration of the violation and there was no evidence that it attempted to conceal the violations.

Penalty: $0 (aggregate for 4 violations)

FERC Order: Pending

NP18-10-000: Electric Reliability Council of Texas, Inc. (ERCOT)

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