GB/T 21222-2007 (English Version) PDF

Standard No.: GB/T 21222-2007
Language: Chinese, Available in English version
Release Date: 2007
Published By: General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
Latest: GB/T 21222-2007

Scope: 1.1 This standard specifies two test methods A and B, which are used to evaluate the electric strength of insulating liquids subjected to standard lightning pulses in a divergent field. Method A is based on a step-by-step test procedure for evaluating the pulse breakdown voltage under specified conditions. Method B is a statistical test to test assumptions about the probability of pulse breakdown of insulating liquids at a given voltage level. 1.2 Both methods are applicable to unused or used insulating liquid, the viscosity of which should be lower than 700mm²/s at 40℃. Both methods can use positive and negative pulses. There are no special regulations regarding the preparation of liquid samples as long as they meet the requirements for industrial use. However, tests performed on samples before and after treatment can show how effective the treatment is. 1.3 Two methods are mainly used to establish standard procedures for evaluating the impulse electric strength of insulating liquids. These procedures are used to distinguish between different dielectric liquids, and can also be used to detect changes in the chemical composition of the liquid when the manufacturing process or raw material changes, and the resulting change in properties.

GB/T 21222-2007 Referenced Document

GB/T 16927.1-1997 High-voltage test techniques. Part 1: General test requirements
GB/T 16927.2-1997 High-voltage test techniques. Part 2: Measuring systems
GB/T 311.6-2005 Voltage measurement by means of standard air gaps
IEC 60060-3 High voltage test techniques - Part 3: Definitions and requirements for on-site testing
IEC 60060-4 High-voltage test techniques. Part 4 : Application guide for measuring devices
IEC 60475 Method of sampling insulating liquids*， 2022-05-25 Update

2007 GB/T 21222-2007 Methods for the determination of the lightning impulse breakdown voltage of insulating liquids