Abstract
In this study, changes in the capacitance of MOV-based arresters resulting from thermal stresses are analysed. Low-voltage MOV samples are artificially degraded at different thermal stresses, while the simultaneously applied ac field was kept constant. Prior to ANOVA being applied, the change in capacitance measured at room temperature, before and after degradation process, is tested for compliance with normality using Anderson-Darling test. Results show significant reduction in capacitance after electro-thermal degradation.