Energy and Power
8 steps to begin basic circuit design
What do we need to know? Clearly, plunging into calculations of cable size is of little value unless the type of cable and its method of installation is known. This, in turn, will depend on the installation’s environment. At the… Read more
Apr 11, 2014 | By Edvard Csanyi
Cables
Selection Of Number Of Cable Cores With Emphasis On Sizing Parameters
The selection of number of cable cores basically depends on the type of system where it is going to be installed. Generally we have two types of systems: A perfectly balanced system and A system with some degree of unbalance… Read more
Sep 06, 2013 | By Chirag Singhal
Energy and Power
Switching contactor and effect of long control lines
In accordance with IEC 60947-4-1 and IEC 60947-5-1, the normal control voltage range of power and control contactors lies between 85 … 110 % of the rated control voltage. Within these limits contactors pull-in perfectly. Frequently contactors are offered with… Read more
May 15, 2013 | By Edvard Csanyi
Cables
Differences Between Earthed and Unearthed Cables
In HT electrical distribution, the system can be earthed or unearthed. The selection of unearthed or earthed cable depends on distribution system. If such system is earthed, then we have to use cable which is manufactured for earthed system. (which… Read more
Jan 21, 2013 | By Jignesh Parmar
Cables
Short Overview of LV Cable Terminations
A termination is the electrical and physical connection of a cable end to a piece of equipment or another cable. A splice is the electrical connection of a cable end to another cable with the same cable number. Cable terminations (splices) are… Read more
Oct 27, 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
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 The method of protection against indirect contact hazards according to… Read more
Jul 30, 2012 | By Edvard Csanyi
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 set of conditions. These conditions include the electrical characteristics of… Read more
Jul 27, 2012 | By Edvard Csanyi
Cables
Locating underground electrical cable faults
Before attempting to locate underground cable faults on direct buried primary cable, it is necessary to know where the cable is located and what route it takes. If the fault is on secondary cable, knowing the exact route is even… Read more
Jul 13, 2012 | By Edvard Csanyi
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 keep the voltage drop (due to impedance of cable conductor)… Read more
May 17, 2012 | By Asif Eqbal
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 current continuously at the designed ambient temperature and laying condition. Ampacity… Read more
May 13, 2012 | By Asif Eqbal
Cables
Measurement of insulation resistance (IR)
The measurement of insulation resistance is a common routine test performed on all types of electrical wires and cables. As a production test, this test is often used as a customer acceptance test, with minimum insulation resistance per unit length… Read more
Apr 28, 2012 | By Jignesh Parmar
Medium Voltage
Erection Procedures For Medium Voltage Switchgear
Before commencing erection of medium voltage (MV) switchgear check that all connections are tight on busbars and on main and auxiliary circuits. Examine the insulation carefully, because there have been cases of burned out connections due to failure to observe… Read more
Apr 03, 2012 | By Edvard Csanyi
Energy and Power
Using Core-Balance Current Transformer For Earth Fault Protection
The core-balance current transformer (or CBCT) is normally of the ring type, through the centre of which is passed cable that forms the primary winding. An earth fault relay, connected to the secondary winding, is energised only when there is… Read more
Dec 28, 2011 | By Edvard Csanyi
Cables
Direct high voltage testing of cable insulation systems
DC testing has been accepted for many years as the standard field method for performing high-voltage tests on cable insulation systems. Whenever DC testing is performed, full consideration should be given to the fact that steady-state direct voltage creates within… Read more
Nov 19, 2011 | By Edvard Csanyi
