NOTICE DATE:  August 5, 2015
NOTICE TYPE:  M-A080515-01 Operations
SHORT DESCRIPTION:  Proposal to Retire Liggett Switching Station Special Protection System
INTENDED AUDIENCE:  ERCOT Market Participants
DAY AFFECTED:  Comments due August 17, 2015

LONG DESCRIPTION:  ERCOT has received a proposal to retire the Liggett Switching Station Special Protection System (SPS) from Oncor Electric Delivery Company (Oncor). The Liggett SPS was designed to automatically insert a 5-ohm reactor in series with each of the Liggett - Hackberry 138 kV lines for the purpose of eliminating overload conditions.


The proposal to disable the Liggett Switching Station SPS is currently under review by ERCOT. Comments on the proposal are due by August 17, 2015 and should be submitted to [log in to unmask]<mailto:[log in to unmask]>  using the attached comment form.  Any questions or concerns submitted by this date will be addressed by ERCOT or Oncor.

In the interim, to effectively manage overloads on the Liggett - Hackberry 138 kV lines, Oncor has proposed to disable the Liggett SPS and manually insert the series reactors on August 7,2015 at 10:00 a.m. Oncor has indicated that the series reactors on the Liggett - Hackberry 138 kV lines can be operated manually with supervisory control. ERCOT Outage Scheduler will be used to track these switching actions.


ACTION REQUIRED:  Any comments to this proposal are due to ERCOT by August 17, 2015, using the attached form.
ADDITIONAL INFORMATION:  Information regarding all SPSs can be found in the "Special Protection Systems and Remedial Action Plans" portlet located on the Long-Term Planning<https://mis.ercot.com/pps/tibco/mis/Pages/Grid+Information/Long+Term+Planning> page of ERCOT's Market Information System (MIS). 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]<mailto:[log in to unmask]>.
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