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…
Power Transformer Protection Author: Velimir Lackovic The advancement of electrical power systems has led to a wide range of power transformers. The rating of these devices ranges from a few kVA to several hundred MVA. The protection provided by a power transformer varies with the application. In the case of a fault within the power…
Industrial System Protection Author: Velimir Lackovic The development of industrial and commercial electrical power systems has created the need to improve their reliability. The costs associated with outage time costs have also increased dramatically. The use of automation systems in industry and commerce requires advanced power system automation to enhance their overall reliability and efficiency….