Recommendation ITU-T K.151 (01/2022) Electrical safety and lightning protection of medium voltage input and up to ±400 V DC output power system in ICT data centre and telecommunication centre
Summary
History
FOREWORD
Table of Contents
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 Reference configuration
     6.1 Typical configuration of MV-PECS
     6.2 The consideration for electrical safety
          6.2.1 Influencing factors
          6.2.2 Pollution degree
          6.2.3 Overvoltage category (OVC)
          6.2.4 Determination of impulse withstand voltage and temporary overvoltage
          6.2.5 Determination of the system voltage
          6.2.6 Components bridging insulation
          6.2.7 Insulation to the surroundings
     6.3 The ports susceptible to lightning surge
7 Earthing and bonding
     7.1 General consideration
     7.2 Earthing configuration for low voltage DC output of MV-PECS
          7.2.1 IT d.c. system
          7.2.2 TNS d.c. system
8 Electrical safety
     8.1 Protection against electric shock
          8.1.1 General
          8.1.2 Requirements for protection against electric shock
          8.1.3 Provision for basic protection
               8.1.3.1 General
               8.1.3.2 Protection by means of basic insulation of live parts
               8.1.3.3 Protection by means of enclosures or barriers
               8.1.3.4 Protection by means of limitation of touch current and charge
               8.1.3.5 Protection by means of limited voltages
          8.1.4 Provision for fault protection
               8.1.4.1 General
               8.1.4.2 Automatic disconnection of supply
               8.1.4.3 Supplementary insulation
               8.1.4.4 Simple separation between circuits
               8.1.4.5 Electrically protective screening
          8.1.5 Enhanced protection
               8.1.5.1 General
               8.1.5.2 Reinforced insulation
               8.1.5.3 Protective separation between circuits
               8.1.5.4 Protection by means of protective impedance
          8.1.6 Clearance distances
          8.1.7 Creepage distances
               8.1.7.1 Insulating material groups
               8.1.7.2 Determination
          8.1.8 Withstand voltage requirement
          8.1.9 Impulse voltage requirement
          8.1.10 Partial discharge requirement
     8.2 Requirements for protection against fire and thermal hazards
          8.2.1 Components within a circuit representing a fire hazard
          8.2.2 Internal arc classification requirements
9 Lightning surge protection
     9.1 Protection of MV power line
     9.2 Protection of MV input port
     9.3 Protection of LV output port and signal/control ports
Bibliography
<\pre>