Electric Motor
Troubleshooting An Open Circuit Faults in the Control Circuit
– The machine does not start when the start button is pressed. At this point the problem could be mechanical or electrical. We will focus on just the electrical circuit faults for now. This fault could be located in either… Read more
Oct 26, 2015 | By Edvard Csanyi
Energy and Power
The Philosophy Of Breaker Failure Protection
The separation of equipment into zones will only work successfully if the outputs of the protections can be guaranteed to do their job. This makes logical sense. For the bus protection in Figure 1 for example, the breakers X and… Read more
May 29, 2015 | By Edvard Csanyi
Energy and Power
A real life analogy of the jurisdiction of the protection relay
Formally, a relay is a logical element which processes the inputs (mostly voltages and currents) from the system/apparatus and issues a trip decision if a fault within the protection relay‘s jurisdiction is detected. A conceptual diagram of relay is shown… Read more
Feb 09, 2015 | By Edvard Csanyi
Energy and Power
Main short circuit faults occurring in networks and machines
Short-circuits can be defined according to three main characteristics: They may be mechanical: breakdown of conductors or accidental electrical connection between two conductors via a foreign body such as a tool or animal; They may be electrical: following the degradation of… Read more
May 30, 2014 | By Edvard Csanyi
Energy and Power
Impacts of Voltage Dips on Power Quality Problems
Figure 1 shows the profile of a voltage dip, together with the associated definitions. The major cause of voltage dips on a supply system is a fault on the system, that is sufficiently remote electrically that a voltage interruption does… Read more
Jun 07, 2013 | By Edvard Csanyi
High Voltage
Using High-Speed Grounding Switches
Automatic high-speed grounding switches are applied for protection of power transformers when the cost of supplying other protective equipment is deemed unjustifiable and the amount of system disturbance that the high-speed grounding switch creates is judged acceptable. The switches are… Read more
Feb 15, 2013 | By Edvard Csanyi
Energy and Power
Using Protective Relay For Fighting Against Faults
Introduction to Protective Relay Working Principle of Protective Scheme What is Relay? Functions of Protective Relay Desirable qualities of protective relaying Terminology of protective relay History of Protective Relay Types of Relays Types of Relay based on Relay Operation Mechanism… Read more
Dec 17, 2012 | By Jignesh Parmar
Protection
Principles and Characteristics of Distance Protection
Distance relays are one of the most important protection elements in a transmission line. These relays may sometimes be set based in percentages of the line impedances, for example a typical setting for zone 1 is 80% of the impedance… Read more
Nov 13, 2012 | By Edvard Csanyi
Cables
The Good, The Bad and The Ugly Cable Insulation
The fundamental understanding of cable insulation properties forms the foundation for assessment of cable operability. These same fundamentals provide the basis for evaluating whether various electrical and physical tests and measurements are meaningful, cost-effective, and warranted. They are a basis… Read more
Oct 23, 2012 | By Edvard Csanyi
Power Substation
Designing of HV Power Substation and Layout
Introduction Earthing and Bonding Substation Earthing Calculation Methodology (Earthing Materials) Layout of Substation Different Layouts for Substations (single busbar, mesh, 1 1/2 cb) Principle of Substation Layouts (spatial separation, maintenance zones) Components of a Substation (cbs, cts, isolators, insulation, transformers etc.) Substations are the… Read more
Oct 01, 2012 | By sprabakar22
Protection
Transformer differential protection (ANSI 87T)
Transformer differential protection protects against short-circuits between turns of a winding and between windings that correspond to phase-to-phase or three-phase type short-circuits. If there is no earthing connection at the transformer location point, this protection can also be used to… Read more
Sep 05, 2012 | By Edvard Csanyi
Power Substation
Transformers Connected Directly to Generators
Power transformers connected directly to generators can experience excitation and short-circuit conditions beyond the requirements defined by ANSI/IEEE standards. Special design considerations may be necessary to ensure that a power transformer is capable of withstanding the abnormal thermal and mechanical aspects that… Read more
Sep 01, 2012 | By Edvard Csanyi
Energy and Power
High resistance grounding equipment in mining applications
High resistance grounding equipment or permanently installed electrical distribution systems used in mines should be selected and applied as recommended for process industries. When mobile equipment is connected to the distribution system the grounding equipment and the ground fault protection should be designed… Read more
Aug 22, 2012 | By Edvard Csanyi
Energy and Power
Isolating the Fault With Time-based Discrimination
Protection functions form a consistent system depending on the overall structure of the power distribution system and the neutral earthing arrangement. They should therefore be viewed as a system based on the principle of discrimination, which consists of isolating the… Read more
Jul 22, 2012 | By Edvard Csanyi
Cables
Mark the ground with an X and say Dig Here!
No matter what method is used for fault locating on direct buried underground cable, at some point an “x” must be marked on the ground to say “dig here.” The most commonly used prelocation methods such as arc reflection or… Read more
Jul 18, 2012 | By Edvard Csanyi
