Hi folks, great board here. I have a couple of varistors that blew. The one next to the blown ones says S14 , K130 , 0009. During some googling, I found that the 14 is the diameter of the varistor in mm and the 130 is its voltage rating. I have found some varistors on Ebay that say 14mm 680volts. My first question is it alright to use a varistors with a higher rating than the old one. I'm assuming the diameter is not as critical (if it fits) as the voltage rating? Also what is the best way to test a varistor? Can I do it in circuit? I have a 500vdc megger. would that help? Thank You for your time!