Electrical Lectures
Fundamental Characteristics of Circuit Breaker
The fundamental characteristics of a circuit breaker are: Its rated voltage Ue Its rated current In Its tripping current level adjustment ranges for overload protection (Ir or Irth) and for short… Read more
Jun 05, 2012 | By Edvard
Energy and Power
Understanding Vector Group of Transformer (2)
Continued from first part Understanding Vector Group of Transformer (part 1) Vector Groups are the IEC method of categorizing the primary and secondary winding configurations of 3-phase transformers. Windings can… Read more
Jun 04, 2012 | By jiguparmar
Energy and Power
Understanding Vector Group of Transformer (Part 1)
Three phase transformer consists of three sets of primary windings, one for each phase, and three sets of secondary windings wound on the same iron core. Separate single-phase transformers can… Read more
Jun 03, 2012 | By jiguparmar
Energy and Power
Process Design Basics for Station Facility
The purpose of this article is to establish the design basis electrical system Front End Engineering Design (FEED) and data design or standards uses in the gathering stations facility will… Read more
May 25, 2012 | By ivan.kurniawan
Energy and Power
Special considerations when selecting transformer protection
Current transformer ratio selection and performance require special attention when applying transformer protection. Unique factors associated with transformers, including its winding ratios, magnetizing inrush current, and the presence of winding… Read more
May 19, 2012 | By Edvard
Cables
Sizing of power cables for circuit breaker controlled feeders (part 3)
Continued from article Sizing of power cables for circuit breaker controlled feeders (part 2) This criterion is applied so that the cross sectional area of the cable is sufficient to… Read more
May 17, 2012 | By Asif Eqbal
Electrical Lectures
Power Measurement In AC Circuits
Power measurement in AC circuits can be quite a bit more complex than with DC circuits for the simple reason that phase shift complicates the matter beyond multiplying voltage by current… Read more
May 15, 2012 | By Edvard
Energy and Power
Introduction to instrument transformers
Instrument transformers (ITs) are designed to transform voltage of current from the high values in the transmission and distribution systems to the low values that can be utilized by low… Read more
May 14, 2012 | By Edvard
Cables
Sizing of power cables for circuit breaker controlled feeders (part 2)
Continued from article Sizing of power cables for circuit breaker controlled feeders (part 1) This criterion is applied so that cross section of the cable can carry the required load… Read more
May 13, 2012 | By Asif Eqbal
Energy and Power
Overvoltages Caused by Indirect Lightning Strokes
A direct stroke is defined as a lightning stroke when it hits a shield wire, a tower, or a phase conductor. An insulator string is stressed by very high voltages… Read more
May 08, 2012 | By Edvard
Energy and Power
Using AC and DC together in electrical system?
There are a number of issues to using AC and DC together in the same electrical system. Briefly, they are: circuit boxes and hardware, outlets, wiring schemes and sizes, and switches. The Electrical… Read more
May 05, 2012 | By Edvard
Energy and Power
Types of Residual Current Devices (RCD)
For domestic applications only the first five of the below listed residual current devices (RCD) need to be considered. For industrial and commercial buildings all of the classifications need to… Read more
May 03, 2012 | By Edvard
Energy and Power
Time relays setting ranges explained in details
Time relays are used in control switching operations involving time delay. Most of these time relays have multiple time setting ranges and most of them are explained below. Time relays… Read more
Apr 30, 2012 | By Edvard
Energy and Power
Overview Of Electrical Loads In Building
The electrical design professional should determine a building’s electrical load characteristics early in the preliminary design stage of the building to select the proper power distribution system and equipment having… Read more
Apr 27, 2012 | By Edvard
Energy and Power
System protection and safety coordination definitions
The objective of system protection is to detect faults and to selectively isolate faulted parts of the system. It must also permit short clearance times to limit the fault power… Read more
Apr 16, 2012 | By Edvard
