Why Test Surge Arresters? 

Mike Horning explains why it is essential to a test transformer surge arresters. Mike is a Senior Transformer Advisor and Instructor at SDMyers.
Transcription:
A surge arrester is a protected device. They are typically called upon to be an insulator most of the time, but during over-voltage situations, they act as a conductor. Now, the test you do for this is not a performance test. We're not going to apply a voltage that is going to cause the arrester to be a conductor. We're going to do a test on its insulating properties. We want to make sure this surge arrester is still a good insulator. It's doing its job properly, will not discharge at a lower voltage than it's designed to discharge at. And so we typically look at watts losses and we don't want the losses to be too high. Most of that information is model type specific and they're in the programs. For instance, in the Dobel software that we use, the limits are built into the software. We'll test them, we'll test the arrestor at a voltage below it's MCOV rating, which is the maximum constant operating voltage. We don't want to test at a voltage higher than what's recommended or the test results will show probably excessive losses, which will then lead us to believe the arrestor has a problem when in fact the only thing we did is tested at too high of a voltage.
Stay up to date on SDMyers content:
SDMyers Website - www.sdmyers.com/
Facebook - / sdmyersllc
LinkedIn - / sdmyers
#SurgeArresters #SDMyers #SubjectMatterExpert