Medium-voltage (MV) cables serve as the backbone of a distribution system, playing a vital role in ensuring the reliable supply of electricity. However, maintaining this extensive network comes at a significant cost for operators. Off-line partial discharge (PD) testing emerges as a valuable tool in managing operating costs and enhancing the reliability of MV cable systems. By transitioning from traditional …
This article reviews current electrical testing methods and trends in the operational health of electric motors in the context of successful predictive maintenance programs. It explains the concepts of static motor testing — testing a motor that is not running — as well as dynamic motor monitoring, which involves analyzing motors while they are in service or operating within their …
In the upcoming years, changes to the existing NERC standards and approved models will be proposed. These changes will impact the synchronous generator (SG) compliance approach and representation. This article outlines proposed changes relevant to generator owners and the impacts on compliance efforts for two such standards: MOD-025 and PRC-019. We also briefly discuss the newly proposed generator model, GENQEC, …
Power cables are important assets in transmission networks for the reliable operation of power systems. To prevent catastrophic failures in underground cables and terminations, it is important to know how to leverage the various types of available sensors that can detect PD and locate the source so that appropriate action can be taken to avoid in-service failures. This article answers …
The majority of the U.S. electric grid was built in the early 20th century. It was initially designed for the one-way transfer of electricity from large fossil-fuel power plants directly to consumers. The grid of that era delivered power from rural areas, where power was generated, to cities, where much of it was consumed. Much has changed in the energy …
There are no one-size-fits-all solutions to the ground fault-protected main circuit breaker issue. Diligent attention to the requirements in the NEC — NFPA 70 and the equipment in the existing installation is required. The 2020 National Electrical Code (NEC – NFPA 70) in Section 230.95 Ground-Fault Protection of Equipment requires ground-fault protection of equipment for solidly grounded wye services of …
The ability of SF₆ to recombine after arcing events — combined with the fact that it is chemically inert, non-toxic in its pure state, non-flammable, and very-high density — makes it an excellent di-electric gas, and sulfur hexafluoride has been used as an insulating medium in the electrical industry since the 1950s. SF6 GAS ENVIRONMENTAL IMPACT SF₆ is a man-made …
Our customers in the NETA community reach out to us with two problems: people and assets. There are just not enough people and technicians to fill the demand in our industry. We consistently work on the people problem with our customers, but the other problem — assets — tends to get put on the back burner. Assets and inventory are …
Transformers are subjected to electrical, thermal, and chemical stresses during their operational life that degrade the insulating oil and solid insulation, cause corrosion and oxidation, and create the conditions for incipient faults to develop, which may ultimately shorten the life of the asset. These ageing processes are necessarily considered during the transformer design phase. However, degradation that occurs faster than …
This is year two for the fifth edition of the CSA Z462, Workplace electrical safety Standard. Are you aware of the changes and updates that could impact your electrical safety program? Have you provided arc flash and shock training to your qualified persons on the new edition? Do you still have questions that need clarification? We marked the first anniversary …