Table of Contents
Thermal Guidelines for Data Processing Environments, Fifth Edition
- Table of Contents 1414
- Preface 1818
- Acknowledgments 2020
- Chapter 1 - Introduction 2222
- Chapter 2 - Environmental Guidelines for Air-Cooled Equipment 3030
- 2.1 Background 3030
- 2.2 New Air-Cooled Equipment Environmental Specifications 3232
- Figure 2.2 2021 recommended and allowable envelopes for Classes A1, A2, A3 and A4. The recommended envelope is for low levels of pollutants verified by coupon measurements as indicated in note 3 of Section 2.2. 3535
- Figure 2.3 2021 recommended and allowable envelopes for Classes A1, A2, A3 and A4. The recommended envelope is for high levels of pollutants verified by coupon measurements as indicated in note 3 of Section 2.2. 3535
- Table 2.1 2021 Thermal Guidelines for Air Cooling— SI Version (I-P Version in Appendix B) 3636
- 2.2.1 Environmental Class Definitions for Air-Cooled Equipment 3838
- Figure 2.4 Climatogram of Class A3 illustrating how dew-point limits modify relative humidity specification limits. 3939
- Figure 2.5 World population distribution by altitude. (Courtesy Bill Rankin, www.radicalcartography.net/howhigh.html) 4141
- Figure 2.6 2021 recommended and allowable envelopes for ASHRAE Class H1. The recommended envelope is for low levels of pollutants verified by coupon measurements as indicated in note 3 of Section 2.2. 4242
- Figure 2.7 2021 recommended and allowable envelopes for ASHRAE Class H1. The recommended envelope is for high levels of pollutants verified by coupon measurements as indicated in note 3 of Section 2.2. 4343
- 2.2.2 Environmental Class Definition for High-Density Air-Cooled Equipment 4242
- 2.2.3 ETSI Environmental Specifications 4545
- 2.3 Guide for the Use and Application of the ASHRAE Data Center Classes 4646
- 2.4 Server Metrics to CONSIDER IN USING Guidelines 4848
- 2.4.1 Server Power Trend versus Ambient Temperature 4949
- 2.4.2 Acoustical Noise Levels versus Ambient Temperature 5151
- 2.4.3 Server Reliability Trend versus Ambient Temperature 5353
- 2.4.4 Server Reliability versus Moisture, Contamination, and Other Temperature Effects 5656
- 2.4.5 Server Performance Trend versus Ambient Temperature 5959
- 2.4.6 Server Cost Trend versus Ambient Temperature 6060
- 2.4.7 Summary of Air-Cooled Equipment Environmental Specifications 6161
- Chapter 3 - Environmental Guidelines for Liquid-Cooled Equipment 6262
- 3.1 ITE Liquid Cooling 6363
- 3.2 Facility Water Supply Temperature Classes for ITE 6767
- Chapter 4 - Facility Temperature and Humidity Measurement 7070
- Chapter 5 - Equipment Placement and Airflow Patterns 7878
- 5.1 Equipment Airflow 7878
- 5.2 Equipment Room Airflow 8080
- 5.2.1 Placement of Cabinets and Rows of Cabinets 8080
- Figure 5.3 View of a hot-aisle/cold-aisle configuration. 8080
- Figure 5.4 Example of hot and cold aisles for raised-floor environments with underfloor cooling. 8181
- Figure 5.5 Example of hot and cold aisles for non-raised-floor environments with overhead cooling. 8181
- Figure 5.6 Cold-aisle containment. 8282
- 5.2.2 Cabinets with Dissimilar Airflow Patterns 8181
- 5.2.3 Aisle Pitch 8282
- Chapter 6 - Equipment Manufacturers’ Heat and Airflow Reporting 8686
- Appendix A - 2021 ASHRAE Environmental Guidelines for ITE— Expanding the Recommended Environmental Envelope 9292
- Table A.1 Comparison of 2004, 2008/2011, 2015, and 2021 Versions of Recommended Envelopes 9292
- Figure A.1 Highlighted in red is the 2021 recommended envelope for a low level of pollutants. 9393
- Figure A.2 Highlighted in red is the 2021 recommended envelope for a high level of pollutants. 9393
- A.1 DRY-BULB TEMPERATURE LIMITS 9595
- A.2 MOISTURE LIMITS 9797
- A.3 ACOUSTICAL NOISE LEVELS 101101
- A.4 Data Center Operation Scenarios for the Recommended Environmental Limits 102102
- Appendix B - 2021 Air-Cooled Equipment Thermal Guidelines (I-P) 104104
- Appendix C - Detailed Flowchart for the Use and Application of the ASHRAE Data Center Classes 110110
- C.1 Notes for Figures 110110
- C.2 Nomenclature for Figures 110110
- Figure C.1 Guidance for applying thermal guidelines. 111111
- Figure C.2 Guidance for applying thermal guidelines to new construction projects. 112112
- Figure C.3 Guidance for applying thermal guidelines to major retrofit projects. 113113
- Figure C.4 Guidance for applying thermal guidelines to existing facilities looking for efficiency gains. 114114
- Appendix D - ESD Research and Static Control Measures 116116
- D.1 ESD Background 116116
- D.2 ESD RESEARCH 116116
- Figure D.1 Walking pattern according to ANSI/ESD STM97.2 (ESDA 2016). (Reprinted with permission of EOS/ESD Association, Inc.) 119119
- Figure D.2 Walking voltage test setup according to ANSI/ESD STM97.2 (ESDA 2016). (Reprinted with permission of EOS/ESD Association, Inc.) 119119
- Table D.1 Types of Flooring and Shoes Used in Test Program 120120
- Table D.2 Flooring and Shoes Defined by Electrical Resistance 121121
- Table D.3 Probabilities of Voltages from Walking Tests Greater than Threshold Values 122122
- D.3 Personnel and Operational Issues 123123
- D.4 Flooring Issues 123123
- D.5 Further Reading 124124
- Appendix E - Research on the Effect of RH and Gaseous Pollutants on ITE Reliability 126126
- Figure E.1 2015 thermal environmental conditions of air entering ITE (A1, A2, A3, and A4 represent different environmental envelopes for ITE). 127127
- Figure E.2 Test specimens: a) standard copper and silver coupons and b) printed circuit board (PCB) coupons. 128128
- Figure E.3 Experimental setup for mixed flowing gas testing. 128128
- Figure E.4 Corrosion thicknesses for copper at 50% rh, 70% rh, and 80% rh. 129129
- Figure E.5 Corrosion thicknesses for silver at 50% rh, 70% rh, and 80% rh. 130130
- E.1 Conclusions From the Research 129129
- Appendix F - Psychrometric Charts 132132
- Figure F.1 Classes A1–A4 allowable and recommended operating conditions for (a) low level of pollutants and (b) high level of pollutants (SI units). 133133
- Figure F.2 Classes A1–A4 allowable and recommended operating conditions for (a) low level of pollutants and (b) high level of pollutants (I-P units). 134134
- Figure F.3 Class H1 allowable and recommended operating conditions for (a) low level of pollutants and (b) high level of pollutants (SI units). 135135
- Figure F.4 Class H1 allowable and recommended operating conditions for (a) low level of pollutants and (b) high level of pollutants (I-P units). 136136
- Appendix G - Altitude Derating Curves 138138
- Appendix H - Practical Example of the Impact of Compressorless Cooling on Hardware Failure Rates 140140
- Figure H.1 Histogram of dry-bulb temperatures for Chicago. 141141
- Figure H.2 Dry-bulb temperatures for Chicago with economization assumptions that include reuse of ITE exhaust heat to maintain a minimum 15°C to 20°C (59°F to 68°F) temperature and a 1.5°C (2.7°F) temperature rise from outdoor air to server inlet. 141141
- Table H.1 Time-Weighted Failure Rate x-Factor Calculations for Air-Side Economization for ITE in Chicago 142142
- Appendix I - ITE Reliability Data for Selected Major U.S. and Global Cities 144144
- I.1 Notes on figures and tables 145145
- Figure I.1 Failure rate projections for air-side economizer for selected U.S. cities. 147147
- Figure I.2 Failure rate projections for water-side economizer for selected U.S. cities. 147147
- Table I.1 Time-Weighted Failure Rate x-Factor Calculations for Class A2 for Air-Side Economization for Selected Major U.S. Cities Assuming 1.5°C (2.7°F) Temperature Rise between Outdoor Ambient Temperature and ITE Inlet Air Temperature 148148
- Table I.2 Time-Weighted Failure Rate x-Factor Calculations for Class A2 for Water-Side Economization for Selected Major U.S. Cities Assuming 9°C (16.2°F) Temperature Rise between Outdoor Ambient Temperature and ITE Inlet Air Temperature 149149
- Figure I.3 Failure rate projections for water-side economizer with dry-cooler-type tower for selected U.S. cities. 150150
- Figure I.4 Failure rate projections for air-side economizer for selected global cities. 150150
- Table I.3 Time-Weighted Failure Rate x-Factor Calculations for Class A2 for Water-Side Dry-Cooler-Type Tower Economization for Selected Major U.S. Cities Assuming 12°C (21.6°F) Temperature Rise between Outdoor Ambient Temperature and ITE Inlet Air ... 151151
- Table I.4 Time-Weighted Failure Rate x-Factor Calculations for Class A2 for Air-Side Economization for Selected Major Global Cities Assuming 1.5°C (2.7°F) Temperature Rise between Outdoor Ambient Temperature and ITE Inlet Air Temperature 152152
- Figure I.5 Failure rate projections for water-side economizer for selected global cities. 153153
- Figure I.6 Failure rate projections for water-side economizer with dry-cooler-type tower for selected global cities. 153153
- Table I.5 Time-Weighted Failure Rate x-Factor Calculations for Class A2 for Water-Side Economization for Selected Major U.S. Cities Assuming 9°C (16.2°F) Temperature Rise between Outdoor Ambient Temperature and ITE Inlet Air Temperature 154154
- Table I.6 Time-Weighted Failure Rate x-Factor Calculations for Class A2 for Water-Side Dry-Cooler-Type Tower Economization for Selected Major U.S. Cities Assuming 12°C (21.6°F) Temperature Rise between Outdoor Ambient Temperature and ITE Inlet Air ... 155155
- Figure I.7 Number of hours per year of chiller operation required for air-side economizer for selected U.S. cities. 156156
- Figure I.8 Number of hours per year of chiller operation required for water-side economizer for selected U.S. cities. 156156
- Figure I.9 Number of hours per year of chiller operation required for water-side dry-cooler economizer for selected U.S.cities. 157157
- Figure I.10 Number of hours per year of chiller operation required for air-side economizer for selected global cities. 157157
- Figure I.11 Number of hours per year of chiller operation required for water-side economizer for selected global cities. 158158
- Figure I.12 Number of hours per year of chiller operation required for water-side dry-cooler economizer for selected global cities. 158158
- Appendix J - OSHA and Personnel Working in High Air Temperatures 160160
- Appendix K - Allowable Server Inlet Temperature Rate of Change 164164
- Figure K.1 Examples of tape equipment inlet air temperature versus time that are compliant with the 5°C (9°F) in an hour temperature change requirement for data center rooms with tape. equipment. 165165
- Figure K.2 Examples of tape equipment inlet air temperature versus time that are noncompliant with the 5°C (9°F) in an hour temperature change requirement for data center rooms with tape equipment. 165165
- Figure K.3 Examples of equipment inlet air temperature versus time that are compliant with the 20°C (36°F) in an hour and the 5°C (9°F) in 15 minutes temperature change requirements for data center rooms that contain other types of ITE not includ... 166166
- Figure K.4 Examples of equipment inlet air temperature versus time that: a) are noncompliant with the 20°C (36°F) in an hour requirement, b) are noncompliant with the 5°C (9°F) in 15 minutes requirement, and c) are noncompliant with 5°C (9°F) i... 166166
- Figure K.5 Example of ITE air inlet temperature rate of change (°C/h) calculated over 1 min, 5 min, 15 min, and 60 min time intervals. 167167
- Figure K.6 Example of time delay between inlet air temperature change to storage array and the corresponding temperature change in HDDs of the storage array. 167167
- Appendix L - Allowable Server Inlet RH Limits versus Maximum Inlet Dry-Bulb Temperature 168168
- Figure L.1 Class A3 climatogram illustrating how dew-point limits modify RH specification limits. 168168
- Figure L.2 Climatogram of recommended ranges for Classes A1 to A4 (see Table 2.1 in Chapter 2 for more details): a) low levels of pollutants and b) high levels of pollutants. 169169
- Figure L.3 Class A1 and A2 operation climatograms. 169169
- Figure L.4 Class A3 and A4 operation climatograms. 170170
- Figure L.5 Class A1 though A4 power off climatogram. 170170
- Figure L.6 Climatogram of recommended ranges for Class H1 (see Table 2.2 in Chapter 2 for more details): a) low levels of pollutants and b) high levels of pollutants. 171171
- Figure L.7 Class H1 operation climatogram. 171171
- References and Bibliography 172172