This part of IEC 60099 covers metal-oxide surge arresters with external series gap (externally gapped line arresters (EGLA) that are applied on overhead transmission and distribution lines, only to protect insulator assemblies from lightning-caused flashovers.<\/p>\n
This standard defines surge arresters to protect the insulator assembly from lightning-caused overvoltages only. Therefore, and since the metal-oxide resistors are not permanently connected to the line, the following items are not considered for this standard:<\/p>\n
switching impulse sparkover voltage;<\/p>\n<\/li>\n
residual voltage at steep current and switching current impulse;<\/p>\n<\/li>\n
thermal stability;<\/p>\n<\/li>\n
long-duration current impulse withstand duty;<\/p>\n<\/li>\n
power-frequency voltage versus time characteristics of an arrester;<\/p>\n<\/li>\n
disconnector test;<\/p>\n<\/li>\n
aging duties by power-frequency voltage.<\/p>\n<\/li>\n<\/ul>\n
Considering the particular design concept and the special application on overhead transmission and distribution lines, some unique requirements and tests are introduced, such as the verification test for coordination between insulator withstand and EGLA protective level, the follow current interrupting test, mechanical load tests, etc.<\/p>\n
Designs with the EGLA’s external series gap installed in parallel to an insulator are not covered by this standard.<\/p>\n
| PDF Pages<\/th>\n | PDF Title<\/th>\n<\/tr>\n | ||||||
|---|---|---|---|---|---|---|---|
| 7<\/td>\n | English \n CONTENTS <\/td>\n<\/tr>\n | ||||||
| 10<\/td>\n | INTRODUCTION Figures \n Figure 1 \u2013 Configuration of an EGLA with insulator and arcing horn <\/td>\n<\/tr>\n | ||||||
| 11<\/td>\n | 1 Scope 2 Normative references <\/td>\n<\/tr>\n | ||||||
| 12<\/td>\n | 3 Terms and definitions <\/td>\n<\/tr>\n | ||||||
| 14<\/td>\n | 4 Identification and classification 4.1 EGLA identification <\/td>\n<\/tr>\n | ||||||
| 15<\/td>\n | 4.2 EGLA classification 5 Standard ratings and service conditions 5.1 Standard rated voltages Tables \n Table 1 \u2013 EGLA classification \u2013 \u201cSeries X\u201d and \u201cSeries Y\u201c Table 2 \u2013 Steps of rated voltages (r.m.s. values) <\/td>\n<\/tr>\n | ||||||
| 16<\/td>\n | 5.2 Standard rated frequencies 5.3 Standard nominal discharge currents 5.4 Service conditions 6 Requirements 6.1 Insulation withstand of the SVU and the complete EGLA <\/td>\n<\/tr>\n | ||||||
| 17<\/td>\n | 6.2 Residual voltages 6.3 High current duty 6.4 Lightning discharge capability 6.5 Short-circuit performance of the SVU 6.6 Mechanical performance <\/td>\n<\/tr>\n | ||||||
| 18<\/td>\n | 6.7 Weather aging of SVU 6.8 Reference voltage of the SVU 6.9 Internal partial discharges 6.10 Coordination between insulator withstand and EGLA protective level 6.11 Follow current interrupting 6.12 Electromagnetic compatibility <\/td>\n<\/tr>\n | ||||||
| 19<\/td>\n | 6.13 End of life 7 General testing procedure 7.1 Measuring equipment and accuracy 7.2 Test samples 8 Type tests 8.1 General <\/td>\n<\/tr>\n | ||||||
| 20<\/td>\n | 8.2 Insulation withstand tests on the SVU housing and on the EGLA with failed SVU Table 3 \u2013 Type tests (all tests to be performed without insulator assembly) <\/td>\n<\/tr>\n | ||||||
| 22<\/td>\n | 8.3 Residual voltage tests <\/td>\n<\/tr>\n | ||||||
| 24<\/td>\n | 8.4 Standard lightning impulse sparkover test <\/td>\n<\/tr>\n | ||||||
| 25<\/td>\n | 8.5 High current impulse withstand test <\/td>\n<\/tr>\n | ||||||
| 26<\/td>\n | 8.6 Lightning discharge capability test <\/td>\n<\/tr>\n | ||||||
| 27<\/td>\n | 8.7 Short-circuit tests <\/td>\n<\/tr>\n | ||||||
| 33<\/td>\n | Table 4 \u2013 Test requirements <\/td>\n<\/tr>\n | ||||||
| 34<\/td>\n | Table 5 \u2013 Required currents for short-circuit tests <\/td>\n<\/tr>\n | ||||||
| 35<\/td>\n | Figure 2 \u2013 Examples of SVU units <\/td>\n<\/tr>\n | ||||||
| 36<\/td>\n | Figure 3 \u2013 Short-circuit test setup <\/td>\n<\/tr>\n | ||||||
| 37<\/td>\n | 8.8 Follow current interrupting test Figure 4 \u2013 Example of a test circuit for re-applying pre-failing circuit immediately before applying the short-circuit test current <\/td>\n<\/tr>\n | ||||||
| 41<\/td>\n | 8.9 Mechanical load tes \nts on the SVU <\/td>\n<\/tr>\n | ||||||
| 46<\/td>\n | Figure 5 \u2013 Thermo-mechanical test <\/td>\n<\/tr>\n | ||||||
| 47<\/td>\n | Figure 6 \u2013 Example of the test arrangement for the thermo-mechanical testand direction of the cantilever load <\/td>\n<\/tr>\n | ||||||
| 48<\/td>\n | Figure 7 \u2013 Test sequence of the water immersion test <\/td>\n<\/tr>\n | ||||||
| 51<\/td>\n | 8.10 Weather aging tests <\/td>\n<\/tr>\n | ||||||
| 52<\/td>\n | 9 Routine tests 9.1 General <\/td>\n<\/tr>\n | ||||||
| 53<\/td>\n | 10 Acceptance tests 10.1 General 10.2 Reference voltage measurement of SVU 10.3 Internal partial discharge test of SVU 10.4 Radio interference voltage (RIV) test Table 6 \u2013 Acceptance tests <\/td>\n<\/tr>\n | ||||||
| 54<\/td>\n | 10.5 Test for coordination between insulator withstand and EGLA protective level Table 7 \u2013 Virtual steepness of wave front of front-of-wave lightning impulses <\/td>\n<\/tr>\n | ||||||
| 55<\/td>\n | 10.6 Follow current interrupting test 10.7 Vibration test on the SVU with attached electrode <\/td>\n<\/tr>\n | ||||||
| 57<\/td>\n | Annex A (informative) \nExample of a test circuit for the follow current interrupting test Figure A.1 \u2013 Example of a test circuit for the follow current interrupting test <\/td>\n<\/tr>\n | ||||||
| 58<\/td>\n | Annex B (normative) \nMechanical considerations Figure B.1 \u2013 Bending moment \u2013 Multi-unit SVU <\/td>\n<\/tr>\n | ||||||
| 60<\/td>\n | Figure B.2 \u2013 SVU unit <\/td>\n<\/tr>\n | ||||||
| 61<\/td>\n | Figure B.3 \u2013 SVU dimensions <\/td>\n<\/tr>\n | ||||||
| 63<\/td>\n | Bibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" Surge arresters – Metal-oxide surge arresters with external series gap (EGLA) for overhead transmission and distribution lines of a.c. systems above 1 kV<\/b><\/p>\n |