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     Construction            
 6     Electrical characteristics      
        6.1     GDT spark-over voltage           
        6.2     GDT glow voltage       
        6.3     GDT arc voltage           
        6.4     GDT d.c. holdover voltage       
        6.5     GDT capacitance         
        6.6     GDT oscillation             
 7     Electrical ratings     
        7.1     GDT surge current capability  
        7.2     a.c. discharge current test      
 8     Application examples          
        8.1     Two-electrode and three-electrode GDT comparison  
        8.2     Surge bonding             
        8.3     GDT pass under protection for a.c. fault conditions      
        8.4     GDTs in a.c. mains applications             
        8.5     Hybrid protectors       
        8.6     GDT thermal switch hybrid     
        8.7     GDT backup air gap hybrid      
        8.8     Cascaded protection 
        8.9     Series connected GDTs for d.c. power applications       
Appendix I – Durability test using "Fast" GDTs    
        I.1                  Testing
Appendix II – Spark-over dark effect    
       II.1     Testing             
Appendix III – GDT component form factors    
      III.1     Introduction  
      III.2     Outlines of GDTs with different form factors   
      III.3     Outline of GDTs with coaxial form factors         
      III.4     Outlines of GDTs with reduced axial length and two-electrodes              
      III.5     Outlines of GDTs with reduced axial length and three-electrodes           
      III.6     General           
Appendix IV – Three-electrode GDT operation in Ethernet circuits    
       IV.1     Introduction 
       IV.2     Three-electrode GDT applied to Ethernet twisted pair
       IV.3     Three-electrode GDT applied to Ethernet powering pair