Cables
Sizing and protection of the neutral conductor (2)
Continued from the first part – Sizing and Protection of the Neutral Conductor (1) If the neutral conductor is correctly sized (including harmonics), no specific protection of the neutral conductor is… Read more
Jul 31, 2012 | By Edvard
Cables
Sizing and protection of the neutral conductor (1)
Sizing (c.s.a.) and the protection of the neutral conductor, apart from its current-carrying requirement, depend on several factors, namely: The type of earthing system, TT, TN, etc. The harmonic currents… Read more
Jul 30, 2012 | By Edvard
Energy and Power
Guidelines to Visual inspection of Electrical Installations
In general terms we are inspecting the installation with regard to personal safety, equpment age, deterioration, equipment corrosion and overload. Suitability and external influence to the power system should also… Read more
Jul 28, 2012 | By Edvard
Cables
Types of Cable Installations in Electrical Network
There are a variety of ways to install power distribution cables. Each method ensures distribution of power with a unique degree of reliability, safety, economy, and quality for any specific… Read more
Jul 27, 2012 | By Edvard
Energy and Power
Overvoltages in the IT system
Electrical networks can be subject to overvoltages of varying origins. Some overvoltages, such as differential mode ones (between live conductors) affect all the earthing systems. This section is particularly concerned… Read more
Jul 26, 2012 | By Edvard
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…. Read more
Jul 25, 2012 | By Edvard
Energy and Power
The main components of an oil circuit breaker and how does it interrupt the arc
They are simple in construction. The major parts of a minimum oil circuit breaker excluding the poles are the base frame,the drive which is constructed as a stored energy opening… Read more
Jul 24, 2012 | By Edvard
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… Read more
Jul 22, 2012 | By Edvard
Energy and Power
Bus Design In Aboveground Substations
Substations can be constructed partly or entirely within aboveground or belowground enclosures. However, cost is high and complexity is increased by fire-protection and heat-removal needs. The following discussion deals with… Read more
Jul 21, 2012 | By Edvard
Energy and Power
Effect of Lightning Strike on Electrical Lines
The foregoing discussion concentrated on the principles of lightning strikes and how their effects can be mitigated. However, lightning strikes on electrical lines or substations are those that cause problems… Read more
Jul 20, 2012 | By Edvard
Electric Motor
AC Adjustable Speed Drive (ASD) – An Overview
The simplest and least expensive way to control the speed of a process or piece of equipment is to operate all the equipment at full speed. Many applications require the… Read more
Jul 19, 2012 | By Edvard
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… Read more
Jul 18, 2012 | By Edvard
High Voltage
Shunt Reactor Used In HV and EHV Systems
Main Power System parameters are System Voltages and Frequency which normally indicate the healthiness level (they indicate the level of Generated active and reactive Powers against the load power requirement)…. Read more
Jul 17, 2012 | By Edvard
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… Read more
Jul 16, 2012 | By Edvard
High Voltage
Autoreclosing in Transmission and Distribution Systems
Two main functions of Utility Electric System Operations department are Control and Protection. Control function deals with all operational aspects involved in efficient and optimal dispatching of available real power… Read more
Jul 15, 2012 | By Edvard
