ME 3.0 to ME 5.0 ME3.0 review scheduled during the Joint NDSWG/NATF meeting in July. There were approximately 180 comments on the ME3.0 paper. Deadline for comments was 8/4. – Comments received from Oncor, AEP, Luminant, Tenaska, CPS, TNMP, LCRA, and CNP – Roughly half of the comments were incorporated in ME4.0 – All comments were addressed in written form and returned to NDSWG 8/17 Joint NDSWG/NATF meeting ME4.0 and the ERCOT responses were discussed 7 modifications to ME4.0 were requested as a result to of the 8/17 meeting ME5.0 contains those 7 modifications

1. All – Language to be included that ERCOT will consult before an Interim update is rejected. New – Language p. 9: ERCOT will consult with data submitters to reschedule or modify all interim updates that cannot be implemented as submitted. In some cases in may be necessary for data submitters to modify some part of the interim update. Rejection of the interim update will be considered a last step and be used only if other coordination efforts fail.

2. AEP – clarification on retirements corresponding to model loads – will they be processed New – Language p22: The field-retirement date should precede the model- retirement date. In addition, the model-retirement date should be associated with a Scheduled or Supplemental model load date. If a TSP mistakenly enters a model- retirement date for an existing piece of equipment that does not match a model load date, ERCOT will contact the data submitter with a suggested correction. Without the correction that piece of equipment may not be included in that model (models are back-loaded with data).

3. All – 12PM vs 12AM clarification New – Language p. 14: Scheduled Model Load Time-of-Day Scheduled Model loads will normally occur at 12:00 AM (0000) on Tuesday, Wednesday or Thursday. The day of the week for first-of-the-month loads will vary. All Scheduled Model loads will occur at 12:00 AM (0000) on the scheduled date for the load

4. All – add cross reference for types of updates not subject to interim rules New – Language p. 7: Interim Updates ERCOT expects requests to modify the Network Model to meet the Protocol timelines for Network Model changes. NOMCRs that are submitted outside of the normal timelines will be classified as Interim Updates and included in the Network Model if they are needed to correct unintentional modeling inconsistencies, are required for system restoration after a storm, are a correction to previously submitted impedances or ratings. Interim Updates will be reported to the Public Utility Commission of Texas (PUCT) Staff and the Independent Market Monitor (IMM). Per Nodal Protocols, Interim Updates will be incorporated in the Network Model at the discretion of ERCOT. Many considerations will be made in determining the overall impact of the Interim update to the Network Operations model. ERCOT has outlined a guideline that will be applied to every requested interim update to consistently assess a level of risk and raise transparency to criteria by which interim updates are evaluated. ERCOT will also critically evaluate other risk items such as system conditions, staffing, volume of requested changes, potential Protocol obligations, etc. prior to determining if the interim update will be accepted. Section II.B.2 contains information about data submissions not subject to Interim Updates.

5. All – Any changes to the ME paper will be vetted with ROS New – Language p. 6: Overview ERCOT Protocols broadly delineate modeling requirements for different segments of the ERCOT market. The information in this document is intended to more clearly define the expectations ERCOT has for market participants as they help to maintain the accuracy of the ERCOT Network Operations Model through the submission of model and outage data. Modifications to this document by ERCOT will be documented and discussed with NDSWG prior to being finalized or implemented in ERCOT business processes.

6. Oncor – Modify 48-hour rule for dynamic ratings New – Language p. 9: Dynamic rating changes for new and existing lines TSPs and REs will be able to dynamically rate a statically rated line or adjust previously submitted dynamic ratings in production within 48 hours. ERCOT is given 24-hours to accept or reject the dynamic rating change request and then another 24-hours to implement the change into production. Model changes that dynamically rate lines will not be subject to Interim Update status.

7. Oncor – Interim Update table is not all-inclusive New – Language p 36: This table is not meant to represent all instances of interim updates.