Low Voltage
Defining Size and Location of Capacitor in Electrical System (2)
Continued from part 1: Defining Size and Location of Capacitor in Electrical System (2) Size of circuit breaker (CB), fuse and conductor of capacitor bank: A. Thermal and magnetic setting of a circuit breaker B. Fuse selection C. Size of… Read more
Mar 11, 2013 | By Jignesh Parmar
Medium Voltage
Things You Should Know About Medium Voltage GIS
Environmental Concerns Safety Concerns Special Handling Procedures Installation Concerns Operation and Maintenance Concerns End of Life / Recycling Concerns Conclusion Medium voltage (5-38 kV) gas insulated switchgear (GIS) differs greatly from the medium voltage AIS – Air insulated switchgear commonly… Read more
Feb 20, 2013 | By Edvard Csanyi
High Voltage
High voltage substations overview (part 1)
High voltage substations are interconnection points within the power transmission and distribution systems between regions and countries. Different applications of substations lead to HV substations with and without power transformers: Step up from a generator voltage level to a high voltage… Read more
Jan 25, 2013 | By Emmanouil Angeladas
Energy and Power
Discrimination between residual current circuit breakers (RCCBs)
The operating principle of the residual current release is basically the detection of an earth fault current, by means of a toroid transformer which embraces all the live conductors, included the neutral if distributed. In absence of an earth fault,… Read more
Jan 11, 2013 | By Edvard Csanyi
Energy and Power
Short-Circuit Switching Capacity Definition
The switching capacity is the r.m.s value of a current at a given power factor cosφ as well as a given rated voltage at which a switchgear or a fuse can still shut-off under specified conditions in an operationally safe… Read more
Dec 20, 2012 | 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
High Voltage
Methods of Controlling Lightning Overvoltages in HV
For well shielded transmission lines, the backflashover condition, close to the substation, is of prime concern for determining the location and number of surge arresters required to achieve insulation coordination of the substation for lightning surges. The risk of a… Read more
Dec 08, 2012 | By Edvard Csanyi
Energy and Power
Application of Circuit Breakers in IT Networks
IT supplies are used to prevent that a ground fault leads to immediate disconnection of the affected circuit like in a grounded system. Although a first ground fault results in a displacement of the potential of the entire supply, continued… Read more
Nov 03, 2012 | By Edvard Csanyi
Energy and Power
Smart and safe protective shutdown of LV system with selectivity
From the point of view of the operational safety and reliability of an entire low-voltage installation, it is usually desirable to specifically isolate the part of a system affected by a short-circuit in order to prevent spreading of the fault. Selectivity… Read more
Oct 30, 2012 | By Edvard Csanyi
Energy and Power
Simplify Downstream Installation with Cascading
Cascading provides circuit breakers placed downstream of a limiting circuit breaker with an enhanced breaking capacity. The limiting circuit breaker helps the circuit breaker placed downstream by limiting high short-circuit currents. Cascading makes it possible to use a circuit-breaker with… Read more
Oct 16, 2012 | By Edvard Csanyi
Protection
Overcurrent protection of transformer (NEC 450.3)
The overcurrent protection required for transformers is consider for Protection of Transformer only. Such overcurrent protection will not necessarily protect the primary or secondary conductors or equipment connected on the secondary side of the transformer. Introduction Overcurrent protection of transformers… Read more
Oct 08, 2012 | By Jignesh Parmar
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
Delayed Auto-Reclosing On EHV Systems
On highly interconnected transmission systems, where the loss of a single line is unlikely to cause two sections of the system to drift apart significantly and lose synchronism, delayed auto-reclosing can be employed. Dead times of the order of 5s-60s are commonly used…. Read more
Aug 11, 2012 | By Edvard Csanyi
Energy and Power
The major components of an Air Circuit Breaker and the Arc Interruption
The basic characteristics for air magnetic circuit breakers are maximum rationalization and constructional simplicity. The major components of such breakers are: the poles, the arc chutes, the base frame, the operating mechanism. The operating mechanism construction and parts are similar to that of… Read more
Jul 25, 2012 | By Edvard Csanyi
Medium Voltage
Field Inspection of New Medium-Voltage Switchgear
Step Description of what you should do 1.1 Check switchgear assembly for alignment, levelness, and tightness of all bolting. 1.2 Check all equipment for the removal of blocking, supports, temporary ties, and temporary jumper wires. 1.3 Check control power transformer… Read more
Jul 16, 2012 | By Edvard Csanyi
