How frequently are you performing maintenance on your Medium Voltage Vacuum Circuit Breaker?

The International Electrical Testing Association (NETA) publishes a “Frequency of Maintenance Tests” Appendix as part the ANSI/NETA-MTS Specification. This specification is updated every four years. A review of this appendix first requires that we have a bit of information before we can determine the “Frequency”. We first need to know what the equipment reliability requirement [...]