Operation and Maintenance of a Gas Insulated Substation Author: Velimir Lackovic This course presents several real life experiences from existing GIS technology that has been in service for a number of years. It describes the nature and sources of defects including their repair and maintenance. It covers routine measurement methods to determine the quality of…
Recent Trends and Innovations in Arc Flash Assessments Author: Velimir Lackovic New equipment and innovations have led to significant improvements in arc flash systems and have created a safer work environment for the staff involved in maintenance of electrical equipment. In addition, some older established methods are being used to make equipment safer. Coordination of…
Arc Flash Resistant Equipment Author: Velimir Lackovic Arc flash resistant equipment is designed to withstand the impact of internal arcing fault as defined by the requirements of IEEE Guide C37.20.7-2007. In the 1970s, an interest started in Europe in assessing electrical equipment under internal arcing, which lead to development of the IEC standard. This research…
Arc Flash Hazard Calculations in DC systems Author: Velimir Lackovic The current international and national standards governing arc flash hazards do not adequately address DC systems. IEEE 1584 does not discuss arc flash hazard calculations in the DC systems, and NFPA-70E- 2000 only provides a short calculation method. Although the necessary calculation steps for DC…
Unit Protection of Feeders Author: Velimir Lackovic This online engineering PDH course presents the concepts of electrical unit protection and their particular applications to high voltage feeders. The graded overcurrent protection design, though quite simple, does not meet all the protection demands of an electrical power system. Application issues are experienced for two reasons: 1)…
Protection Relay Testing and Commissioning Author: Velimir Lackovic The testing and verification of protection devices and their various arrangements introduces a number of issues for the design engineer. An important limitation is these devices cannot be tested under normal operating conditions because they are designed to operate under fault conditions. This problem is worsened by…