NOTICE DATE: June 1, 2015

NOTICE TYPE: W-A060115-01 Operations

SHORT DESCRIPTION: 2015 Summer/Fall Voltage Profiles

INTENDED AUDIENCE: ERCOT Market Participants

DAY AFFECTED: June 1, 2015

LONG DESCRIPTION: ERCOT has posted the 2015 Summer (June 1 – August 31) and Fall (September 1 – November 30) Voltage Profiles for each Generation Resource Point of Interconnection (POI). ERCOT and the Transmission Service Providers (TSPs) derived these Voltage Profiles after a series of joint studies and one meeting.

All NERC Registered Generator Operators are hereby directed to comply with the Voltage Profile in automatic voltage control mode. In accordance with Nodal Operating Guides Section 2.7.4.1, Maintaining System Voltage, Generation Resources required to provide Voltage Support Service (VSS) must maintain transmission system voltage at the POI within 2% of the Voltage Profile when operating at less than the maximum reactive capability of the Generation Resource. Also, in accordance with Protocols Section 3.15.3, QSE Responsibilities Related to Voltage Support, each QSE must operate its Generation Resources in automatic voltage control mode and at the posted Voltage Profile unless otherwise directed by the interconnected TSP or ERCOT. A QSE should immediately notify ERCOT and the interconnected TSP if it’s Generation Resource cannot operate within 2% of the assigned Voltage Profile or alternate voltage schedule directed by the interconnected TSP or ERCOT.

In accordance with NERC Reliability Standard VAR-001-4 R5, the spreadsheet posted on the Market Information System (MIS) lists Voltage Profile for every generation resource at its POI in columns (G, K) and (T, X). In cases where the POI is located at low side the step-up transformer, Voltage Profile at the corresponding high side are listed in columns (L, M) and (Y, Z).

ADDITIONAL INFORMATION: Information regarding 2015 Summer/Fall Voltage Profiles can be found on the ERCOT Market Information System (MIS) under Voltage Profiles on the Grid/Transmission page. A Digital Certificate is required to access the MIS.

CONTACT: If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at [log in to unmask].

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