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From: ERCOT Client Services
Sent: Tuesday, April 02, 2019 10:50 AM
To: ERCOT Client Services <[log in to unmask]>
Cc: ERCOT Account Managers <[log in to unmask]>; Market Support Services <[log in to unmask]>
Subject: W-A040219-01 Annual Under-Frequency Load Shedding survey of Transmission Operators

NOTICE DATE:  April 2, 2019
NOTICE TYPE:  W-A040219-01 Operations
SHORT DESCRIPTION:  Annual Under-Frequency Load Shedding survey of Transmission Operators
INTENDED AUDIENCE:  ERCOT Transmission Operators
DAY AFFECTED:  June 12, 2019
LONG DESCRIPTION:  In accordance with Nodal Operating Guides Section 2.6.1, Automatic Firm Load Shedding, ERCOT requests that Transmission Operators (TOs) complete the attached Under-Frequency Load Shedding (UFLS) survey.  Please note that Nodal Operating Guide Revision Request (NOGRR) 178, Clarification of Automatic Under-Frequency Load Shed Requirement, was adopted in November 2018.  Among other things, NOGRR 178 streamlined the survey process to be completed by TOs and modified the under-frequency response tiers to be cumulative in their load relief percentages (details below).
The survey must be completed for the test hour of May 9, 2019 at 11:00 A.M Central Prevailing Time (CPT).  Each TO is required to make arrangements to secure the measured load for the test hour.
ADDITIONAL INFORMATION:  ERCOT has prepared the attached survey form for use by TOs to report data collected from the test hour of May 9, 2019 at 11:00 A.M CPT.

*         If the data cannot be collected for the test hour for any reason, including equipment failure, please submit the information for an hour that is as close to the test hour as possible.



*         Please include the total load to trip for Under Frequency Relay set points of 59.3 Hz, 58.9 Hz and 58.5 Hz corresponding to load relief of at least 5%, 15% and 25%, respectively.



*         TOs are asked to list the ERCOT-registered Transmission and/or Distribution Service Providers (TDSPs) included in their survey for which they are the designated TO.  Please list these TDSPs by Load area or using the comment section of the survey.



*         Please complete both tabs on the survey form.  The second tab includes additional relay information.



*         Please use "2019_UFLS_Survey_Form" in naming the completed survey form and the same naming convention for any other supporting documentation submitted with the survey.

ACTION REQUIRED: ERCOT appreciates your cooperation and asks that the attached survey be submitted no later than June 12, 2019 via e-mail to [log in to unmask]<mailto:[log in to unmask]>.
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]>.
If you are receiving email from a public ERCOT distribution list that you no longer wish to receive, please follow this link in order to unsubscribe from this list:  http://lists.ercot.com<http://lists.ercot.com/>.



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