NOTICE DATE: November 9, 2011

NOTICE TYPE: W-A110911-01 Extracts – Wholesale

SHORT DESCRIPTION: XSD/XML changes to Settlement Extracts

INTENDED AUDIENCE: ERCOT Market Participants using XML Settlement files

DAY AFFECTED: October 26, 2011

LONG DESCRIPTION: ERCOT made an XSD change beginning with the October 26, 2011, extract posting which resulted in the change of the ‘num’ tag from XML files to be optional as opposed to required. These changes were implemented for performance improvements in our file writing processes. Although this change was not previously communicated to the market, this XSD change is backwards compatible against all file versions. ERCOT apologizes for any issues this update has caused with file loading processes.

The updated XSDs have been posted and should be downloaded and applied to Market Participant databases:

· Settlement Extracts XSD (applies to the following extracts)

· Real-Time Market Market Operating Day Extract (RTM MODE)

· Real-Time Market Consolidated Operating Day Extract (RTM CODE)

· Day-Ahead Market Market Operating Day Extract (DAM MODE)

· Day-Ahead Market Consolidated Operating Day Extract (DAM CODE)

· Settlement Inputs Data Extract XSD (SID)

· Public Reference Data Extract XSD(PRDE)

· Settlements Calendar XSD

ADDITIONAL INFORMATION: This change is specific to the XML files; there were no changes made to the DDL or the CSV files. The updated XSDs can be found on the ERCOT website, under Services, at http://www.ercot.com/services/mdt/xsds/.

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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