Issue link: https://cp.revolio.com/i/488587
26 | THE DATA CENTER JOURNAL www.datacenterjournal.com www.datacenterjournal.com 26 | THE DATA CENTER JOURNAL ment of standards, updating the relevant sections of the Handbooks, providing relevant, topical and timely publications, organizing programs for the bi-annual meetings, and reviewing technical papers. e committee has been particularly active in the special publications depart- ment, for which 11 books have been issued (see sidebar), another very close to being issued, and another two currently being worked on. TC9.9 has also sponsored the presentation of over 100 peer-reviewed papers and over 100 seminar presentations at ASHRAE meetings since its inception. tc9.9 sPonsoreD guiDelines Thermal Guidelines, TC9.9's first publication TC9.9's first publication, ermal Guidelines for Data Processing Environ- ments, was a groundbreaking one that combined the expertise of leaders in both the cooling and IT industries to provide guidance in the areas of environmental inlet conditions for IT equipment, and strategies for cooling this equipment, as well as testing and monitoring. e book was an instant success, and now in its third edition, continues to be THE unbiased vendor-neutral consensus design criteria for the IT and Data Center Facilities industries having sold over 5,000 copies worldwide, including translations into Chinese and soon also in Spanish. ashrae sPonsoreD stanDarDs ASHRAE Standard 127 ASHRAE Standard 127, Method of Testing for Rating Computer and Data Processing Room Unitary Air Condition- ers, focuses on providing a standard rating system for CRAC and CRAH units. is standard is typically updated every 5 years, and the most recent update was in 2012. e 2012 revision had many updates over the 2007 edition, primarily dealing with the fact that chilled water supply tempera- tures and return air temperatures to CRAC and CRAH units have migrated higher in recent years. For instance, while the 2007 version of the CRAH test standard was based on 45°F (7.2°C) chilled water supply temp, the 2012 version is based on 50°F (10°C) chilled water supply. And while the 2007 standard was based on a single chilled water return temperature of 75°F (23.9°C), the 2012 standard has ratings for return temperatures that range between 75°F (23.9°C) and 105°F (40.5°C). Standard 127 has made these changes so that the CRAC and CRAH testing and rating standards would stay current and relevant. AHRI 1360 While TC9.9 was not directly in- volved in the creation of AHRI Standard 1360, Performance Rating of Computer and Data Processing Room Air Condi- tioners, the 2013 version of this standard closely parallels the definitions and much of the content of ASHRAE Standard 127- 2012. In a similar manner, ASHRAE's Recommended and Allowable Ranges for IT Equipment inlets have been adopted by many other standards organizations as 'industry standard'. ASHRAE Standard 90.4P e building industry has been under continued pressure to save energy. A report issued by the EPA in 2004 called attention to the data center industry as an accelerating energy user and large savings opportunity. Prior to 2010 the model energy code (ASHRAE 90.1) excluded data centers (i.e. computer rooms). Because ASHRAE 90.1 had never included data centers before they had limited experience with this specific building application. Conversely, the data center industry had no experience with 90.1. Added to this the data center industry had no end-user representation on the 90.1 committee when the decision add data centers was made. e combination of the 2 resulted in the inclusion of data centers (com- puter rooms) in 90.1. e intent was that it would save energy but 90.1 was too prescriptive resulting in inhibiting energy savings and introducing unacceptable risks to the industry. As a result, a new Standards Com- mittee 90.4 exclusively focused on data centers was convened. e 90.4 committee has been meet- ing for 2 years, and in February 2015, the first public review of the new standard was released. e 90.4 standard is more perfor- mance based than prescriptive in nature, and sets minimum required energy performance for the cooling and electrical infrastructure. e performance metric, defined in the proposed standard, consists of the components of PUE. To encourage the use of systems with efficient part- load operation, minimum efficiencies are required at 50% and 100% of full load op- eration. To encourage the use of warmer supply air temperatures, as well as the use of economizers, the minimum efficiency for the cooling infrastructure is a function of climate zone. imPact on Data centers Design and Construction e impact of TC9.9 publications on the data center industry remains signifi- cant, primarily because the TC knows that in dealing with a dynamic industry, one cannot sit still. ermal Guidelines, for instance, is now in its third edition, and Datacom Equipment Power Trends and Cooling Applications is now on its second edition. ermal Guidelines now provides a range of environmental classes for IT equipment, and by inference as design guidelines for data centers. Two new class- es, Class A3 and A4, were added in 2012, and these allow for inlet temperatures as high as 104°F (40°C ) and 113°F (45°C). ese higher temperatures are 'al- lowable' as opposed to 'recommended', and allow for excursions for a limited number of hours per year to align with ambient excursions. In most climates, Class A3 can be achieved year-round with evaporatively- cooled equipment, and Class A4 can be achieved year-round with ambient air- cooled equipment. In addition, the third edition of ermal Guidelines also introduced Liquid Cooled Environmental Classes to reflect the growth of those particular cooling systems in reaction to the higher densities of load due to a combination of soware, network clustering and hardware technol- ogy enhancements.