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 perform either on-delay or off-delay timing. An arrow is used… Read more
Apr 30, 2012 | By Edvard Csanyi
Measurement of insulation resistance (IR) – Part 2
This article goes into details of insulation resistance values measured by Megger tester on many different kinds of equipment, such as switchgear, electrical wires & cables, electric motors, transmission & distribution lines, and other power system equipment. An insulation tester… Read more
Apr 29, 2012 | By Jignesh Parmar
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
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 adequate power capacity with proper voltage levels, and sufficient space… Read more
Apr 27, 2012 | By Edvard Csanyi
Light Emission Depreciation
Illuminance provided initially by a lighting installation will decrease in a gradual way during its use due to a reduction in lamp lumens, to lamps which burn down, and to accumulation of dirtiness in lamps, luminaires and surfaces of the… Read more
Apr 24, 2012 | By Edvard Csanyi
Direct On Line (DOL) Motor Starter
Different starting methods are employed for starting induction motors because Induction Motor draws more starting current during starting. We use a variety of starters in order to protect the windings from being damaged by the high current flow that is… Read more
Apr 22, 2012 | By Jignesh Parmar
What is the best transformer coolant?
One of the main sources of losses and reasons for temperature rise in various parts of a transformer are the magnetic circuit and windings. So what are the actually reasons of heating the transformer? Responsible for heat generation within the… Read more
Apr 20, 2012 | By Edvard Csanyi
Analog Data Acquisition with Transducers
Transducers measure power system parameters by sampling instrument transformer secondaries. They provide a scaled, low-energy signal that represents a power system quantity that the SA interface controller can easily accept. Transducers also isolate and buffer the SA interface controller from… Read more
Apr 19, 2012 | By Edvard Csanyi
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 and the effect of arcing faults. High power density, high… Read more
Apr 16, 2012 | By Edvard Csanyi
Inspection Of Voltage Drop In Conductors
It is part of the inspection process to ensure that installed conductors have been correctly selected for current carrying capacity and voltage drop. To check the suitability of the current carrying capacity it is simply a matter of looking at… Read more
Apr 15, 2012 | By Edvard Csanyi
What is incident energy caused by arc flash?
Incident energy is the energy per unit area received on a surface located a working distance away from the arc flash location. The working distance is the distance from where the worker to the flash location. This is basically an… Read more
Apr 13, 2012 | By Edvard Csanyi
Key Cyber Security Purposes for the Smart Grid
In the Smart Grid, there are two key purposes for cyber security: Keep electricity flowing to customers, businesses, and industry. For decades, the power system industry has been developing extensive and sophisticated systems and equipment to avoid or shorten power… Read more
Apr 12, 2012 | By Edvard Csanyi
Star-delta motor starter explained in details
Where is Star-Delta motor starter used? Well, the majority of induction motors are started directly on line (DOL), but when very big motors are started in this manner, the large starting current surges produce a disruption in the voltage on… Read more
Apr 10, 2012 | By Jignesh Parmar
Short review of resistance, reactance and impedance
Resistance is essentially friction against the motion of electrons. It is present in all conductors to some extent (except superconductors!), most notably in resistors. When alternating current goes through a resistance, a voltage drop is produced that is in-phase with… Read more
Apr 08, 2012 | By Edvard Csanyi
The direct current (DC) motor – Principle of operation
DC motors have been used in industrial applications for years. Coupled with a DC drive, DC motors provide very precise control DC motors can be used with conveyors, elevators, extruders, marine applications, material handling, paper, plastics, rubber, steel, and textile… Read more
Apr 05, 2012 | By Edvard Csanyi