Arresters ← Knowledge Base What does MCOV or COV (UC) rating of a surge arrester mean? How does MCOV / COV (UC) rating differ from Duty Cycle rating? What field testing does Hubbell Power Systems recommend for distribution arresters? What is the standard lead wire length type? What size wires can be attached using the provided terminal? Are distribution arresters serialized? Are distribution arresters routine tested? Are there any restrictions on how to attach the ground lead connection? What information is included on the arrester nameplates? What if the arrester does not have the minimum leakage (creep) distance needed for my application? What is the difference between a grading ring and a corona ring? What does MCOV rating of a surge arrester mean? What is the difference between a station class and an intermediate arrester? Why is the system grounding type important to consider when selecting the MCOV rating? How do I use the pressure relief rating value in making my arrester selection? What routine maintenance and testing does Hubbell Power Systems recommend for station class surge arresters?