DocumentCode :
1281825
Title :
Determination of safe working 50 Hz AC electrical stresses for ceramics at high temperatures
Author :
Mosley, K. ; Gumley, P.
Author_Institution :
Gracefield Res. Centre, Ind. Res. Ltd., Lower Hutt, New Zealand
Volume :
143
Issue :
6
fYear :
1996
fDate :
11/1/1996 12:00:00 AM
Firstpage :
406
Lastpage :
412
Abstract :
When used as electrical insulation, ceramics in general do not degrade electrically under the influence of time or AC electric stress. However, at high temperatures, conductor (electrode) material can diffuse into the ceramic causing reductions in its electrical strength and resistivity. Experimental work carried out to assess the effect of time on the 50 Hz AC electrical strength of various ceramics at temperatures between 800 and 1140°C is described. Results were obtained for lifetimes of up to 5000 hours. All the ceramics tested, dense alumina, pyrophyllite, alumina and magnesia cement, are available commercially. The influence of electrode materials (heating element alloys) on insulation life is evaluated. Recommendations are made on design procedures for oxide ceramic insulation systems
Keywords :
ceramic insulation; electric breakdown; electric strength; insulation testing; life testing; reliability; 50 Hz; 5000 h; 800 to 1140 C; AC electrical strength; Al2O3; alumina cement; breakdown tests; dense alumina; design procedures; electrode materials influence; high temperatures; insulation life; life testing; long-term strength; magnesia cement; oxide ceramic insulation; pyrophyllite; reliability; resistivity deterioration; safe working AC electrical stresses; time effect; two-parameter Weibull equation;
fLanguage :
English
Journal_Title :
Science, Measurement and Technology, IEE Proceedings -
Publisher :
iet
ISSN :
1350-2344
Type :
jour
DOI :
10.1049/ip-smt:19960712
Filename :
553243
Link To Document :
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