ITU-T L.1241 (09/2023)

1 Scope
2 References
3 Definitions
3.1 Terms defined elsewhere
3.2 Terms defined in this Recommendation
4 Abbreviations and acronyms
5 Conventions
6 Methodology for evaluating performance of a power supply unit
6.1 General measurement conditions
6.1.1 Environmental conditions
6.1.2 Electrical conditions
6.2 Input voltage range
6.3 Input rated frequency and frequency fluctuation range
6.4 Total harmonic distortion (THD) of voltage and current
6.5 No-load power consumption
6.6 Power factor
6.7 Energy efficiency
6.8 PSU level classification
7 Methodology for evaluating the functionality of PSU
7.1 Load distribution management
7.1.1 Load sharing mode
7.1.2 Optimal efficiency automatic adjustment working mode
7.1.3 Active and standby working mode
7.2 Monitoring and control
7.3 Automatic power recovery function
8 Methodology for evaluating safety and protection of PSU
8.1 Insulation resistance and dielectric strength
8.2 Touch current
8.3 Resistance of the protective bonding system
8.4 Flame retardancy of materials
Appendix I Power factor and energy efficiency in some documents
I.1 80 PLUS specification of US Department of Energy
I.2 Ecodesign requirements of the European Union
I.3 Procurement requirements of the People's Republic of (China)
I.4 Certification requirements of China
Appendix II Example of PSU for server testing
II.1 Test items
II.2 Test samples and data
II.2.1 Test on input voltage range, input rated frequency and frequency fluctuation tolerance
II.2.2 Test on the power factor of different rated load
II.2.3 Test on total harmonic distortion (THD) of voltage and current
II.2.4 Test on no-load power consumption and EE of different rated load
II.2.5 Test on load distribution management
Bibliography

Recommendation ITU-T L.1241 provides comprehensive evaluation methods of power supply units configured for servers to evaluate electrical performances, functionalities and safety aspects.