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… Read more
Jul 14, 2012 | By Edvard Csanyi
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… Read more
Jul 13, 2012 | By Edvard Csanyi
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… Read more
Jul 12, 2012 | By Edvard Csanyi
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… Read more
Jul 11, 2012 | By Edvard Csanyi
Delta-Star Transformer Connection Overview
In this type of connection, the primary connected in delta fashion while the secondary current is connected in star. The main use of this connection is to step up the… Read more
Jul 10, 2012 | By jiguparmar
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… Read more
Jul 09, 2012 | By Edvard Csanyi
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… Read more
Jul 07, 2012 | By Edvard Csanyi
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… Read more
Jul 06, 2012 | By jiguparmar
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… Read more
Jul 05, 2012 | By Edvard Csanyi
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… Read more
Jul 04, 2012 | By Bipul Raman
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… Read more
Jul 03, 2012 | By Edvard Csanyi
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… Read more
Jul 02, 2012 | By jiguparmar