Electric Motor
Thermal (Overload) Motor Relay Protection
The majority of winding failures in motor are either indirectly or directly caused by overloading (either prolonged or cyclic), operation on unbalanced supply voltage, or single phasing, which all lead through excessive heating to the deterioration of the winding insulation… Read more
Jul 14, 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
Energy and Power
Definitions from the Standard UL 489 (MCCB)
The requirements of this standard cover molded-case circuit breakers (MCCB), circuit breaker and ground-fault circuit-interrupters, fused circuit breakers, and accessory high-fault protectors. These circuit breakers are specifically intended to provide service entrance, feeder, and branch circuit protection in accordance with… Read more
Jul 12, 2012 | By Edvard Csanyi
High Voltage
Transmission and Distibution Overhead Circuit Faults
Overhead (OH) Transmission circuits are usually HV level (110kV or 115kV and more) to EHV levels (230kV and beyond) and UHV levels (765kV and beyond). OH Distribution systems involve sub-transmission system circuits like 66kV down to 11kV….some times as low… Read more
Jul 11, 2012 | By Edvard Csanyi
Energy and Power
Delta-Star Transformer Connection Overview
The Delta-Star transformer connection is utilized to increase voltage levels and is frequently applied at the end or beginning of high-tension power transmission systems. The primary is configured in a delta arrangement, while the secondary is arranged in a star… Read more
Jul 10, 2012 | By Jignesh Parmar
Energy and Power
The Role of Circuit Breakers in LV/MV Power Systems
A circuit breaker is protective device which is designed to automatically open an electrical circuit thus preventing harm and damages to equipment and personnel. The damages are due to over load, short circuits and sometimes earth faults. Circuit breakers are made… Read more
Jul 09, 2012 | By Edvard Csanyi
Electrical Lectures
Fundamental Concepts of Insulation Testing
Probably 80% of all testing performed in electrical power systems is related to the verification of insulation quality. This technical article briefly describes the fundamental concepts of insulation testing including – insulation behavior, types of tests, and some test procedures…. Read more
Jul 07, 2012 | By Edvard Csanyi
Energy and Power
Delta-Delta Transformer Connection Overview
In this type of connection, both the three phase primary and secondary windings are connected in delta as shown in the Figure 1: The voltages on primary and secondary sides can be shown on the phasor diagram (Figure 2): This… Read more
Jul 06, 2012 | By Jignesh Parmar
Power Substation
Typical noise levels in power substation
Equipment noise levels may be obtained from manufacturers, equipment tendering documents, or test results. The noise level of a substation power transformer is a function of the MVA and BIL rating of the high voltage winding. These transformers typically generate… Read more
Jul 05, 2012 | By Edvard Csanyi
Energy and Power
Too bad Tesla didn’t finish it before he died – Wireless Power Transmission (WPT)
The wireless power transmission (WPT) refers to the efficient transmission of electric power from one point to without use of wire or any other substance. This technology can be used where conventional wires are unaffordable, inconvenient, expensive, hazardous, unwanted or… Read more
Jul 04, 2012 | By Bipul Raman
Electrical Lectures
Voltage vs. Current in a Resistor, Capacitor or Inductor
Elements in an electrical system behave differently if they are exposed to direct current as compared to alternating current. For ease of explanation, the devices have often been compared to similar every day items. Resistors in electrical systems are similar… Read more
Jul 03, 2012 | By Edvard Csanyi
Energy and Power
Autotransformer Connection Explained
An ordinary transformer consists of two windings called primary winding and secondary winding. These two windings are magnetically coupled and electrically isolated. But the transformer in which a part of windings is common to both primary and secondary is called… Read more
Jul 02, 2012 | By Jignesh Parmar
Low Voltage
Assemblies of switchgear and control panels (3)
Continued from 2nd part of article: Assemblies of switchgear and control panels (part 2) Now coverage of distribution panels and switchboards will be presented including molded case circuit breakers (MCCB), safety switches, panelboards, multimetering equipment, ground fault circuit interrupters. Most of the… Read more
Jun 30, 2012 | By Edvard Csanyi
Low Voltage
Assemblies of switchgear and control panels (2)
Continued from 1st part of article: Assemblies of switchgear and control panels (part 1) Other components that are needed for the proper operation of the switchgear or control panel but not necessarily part of the installation or maybe installed remotely are: The batteries… Read more
Jun 29, 2012 | By Edvard Csanyi
Low Voltage
Assemblies of switchgear and control panels
Switchgear and control panels are found in power generating stations, transformer stations, distribution substations, commercial and institutional buildings, industrial plants and factories, refineries, paper mills, metal smelters and any other place where electric energy is utilized or electric power is… Read more
Jun 28, 2012 | By Edvard Csanyi
