EN 60052:2002

INTRODUCTION
1 Scope
2 Normative references
3 Definitions
4 Standard sphere-gap
  4.1 Requirements on shape and surface conditions
  4.2 General arrangement of a sphere-gap for measurement
  4.3 Connections
5 Use of the sphere-gap
  5.1 Condition of the sphere surfaces
  5.2 Irradiation
  5.3 Voltage measurements
6 Reference values in tables 2 and 3
  6.1 Accuracy of values in tables 2 and 3
  6.2 Air density correction factor
  6.3 Humidity correction factor
7 Standard rod-rod gap for measurement of direct voltage
  7.1 General arrangement of a rod-rod gap
  7.2 Reference values
  7.3 Measurement procedure
8 Use of standard air gaps for performance checks of
  approved measuring systems
Annex A (informative) Range of experimental calibrations
        for sphere-gaps
Annex B (informative) Procedure by which the values in
        tables 2 and 3 have been derived from national
        standards and other sources
Annex C (informative) Sources of irradiation
Annex D (informative) Uncertainty and calibration of
        sphere-gaps
Annex ZA (normative) Normative references to international
         publications with their corresponding European
         publications
Bibliography
Figures
Tables

Applies to the construction and use of sphere-gaps for measuring the peak value of alternating, direct and both full standard and longer tail impulse voltages. Peak values of the disruptive voltages in air are given in tabular form. Note: - For high-voltage test techniques, see EN 60.