Title: Clarify Active and Inactive SCED Constraint Reporting
Next Group:
Next Step:
Status: Approved on 10/18/2011
Effective Dates:


Date Gov Body Action Taken Next Steps
10/18/2011 BOARD Approved
09/01/2011 TAC Recommended for Approval ERCOT Board for consideration.
08/18/2011 PRS Recommended for Approval TAC for consideration.
07/21/2011 PRS Recommended for Approval PRS for Impact Analysis review.
05/19/2011 PRS Deferred/Tabled PRS for consideration.

Voting Record

Date Gov Body Motion Result
10/18/2011 BOARD To approve NPRR364 as recommended by TAC in the 9/1/11 TAC Report. Passed
09/01/2011 TAC To recommend approval of NPRR364 as recommended by PRS in the 8/18/11 PRS Report. Passed
08/18/2011 PRS To endorse and forward the 7/21/11 PRS Report and Impact Analysis for NPRR364 to TAC. Passed
07/21/2011 PRS To recommend approval of NPRR364 as amended by the 7/14/11 J Aron comments. Passed
05/19/2011 PRS To to table NPRR364. Passed

Vote tallies here reflect individual votes, not the weight of the votes by market segment. Affirmative votes are not recorded in these vote tallies. For additional details on the voting record, please consult the Recommendation or Action Report, or the official vote tally if available, as posted in the key documents.


Status: Approved
Date Posted: May 4, 2011
Sponsor: ERCOT
Urgent: No
Description: This Nodal Protocol Revision Request (NPRR) clarifies the reporting requirements for Security-Constrained Economic Dispatch (SCED) constraints and aligns the Protocols with current practices.
Reason: This NPRR clarifies Protocol language as to what should be reported regarding transmission constraint information. Network Security Analysis (NSA) is the application used to activate different constraints for economic dispatch by SCED. A constraint consists of a contingency and a monitored Transmission Element paired together. Pursuant to Protocol requirements, the NSA results are currently provided on the Market Information System (MIS) Secure Area; however, the delineation of "active" versus "inactive" is not clear in the current Protocol language. As an example, an inactive constraint is not one in which ERCOT has determined to be inaccurate or inappropriate but rather one that is present in the Transmission Constraint Manager (TCM) that has not been selected for SCED resolution by ERCOT. This NPRR provides a firm delineation for active and inactive constraints, and separates the concept from contingencies that have been rendered ineligible due to being inaccurate or inappropriate. Such invalid contingencies, or contingencies identified by ERCOT as being incorrectly defined or otherwise in error, are already being posted to the MIS per Section per paragraph (6) of Section 5.5.1, Security Sequence.

Key Documents

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