IEC TS 60815-3:2008

FOREWORD
1 Scope and object
2 Normative references
3 Terms, definitions and abbreviations
   3.1 Terms and definitions
   3.2 Abbreviations
4 Principles
5 Materials
   5.1 General information on common polymer housing
        materials
   5.2 Issues specific to polymer housing materials under
        pollution
        5.2.1 Reduction of creepage distance
        5.2.2 Extreme pollution
6 Site severity determination
7 Determination of the reference USCD
8 General recommendations for polymer profiles
9 Checking of profile parameters
   9.1 General remark
   9.2 Alternating sheds and shed overhang
   9.3 Spacing versus shed overhang
   9.4 Minimum distance between sheds
   9.5 Creepage distance versus clearance
   9.6 Shed angle
   9.7 Creepage factor
10 Correction of RUSCD
   10.1 Correction for altitude K[a]
   10.2 Correction for insulator diameter K[ad]
11 Determination of the final minimum creepage distance
12 Confirmation by testing
Annex A (informative) - Background information on pollution
        induced degradation of polymer
Bibliography

IEC/TS 60815-3:2008(E) is applicable to the selection of polymer insulators for a.c. systems, and the determination of their relevant dimensions, to be used in high voltage systems with respect to pollution. This part of IEC/TS 60815 gives specific guidelines and principles to arrive at an informed judgement on the probable behaviour of a given insulator in certain pollution environments.