Anti Pumping And Lockout Relays
What is ANSI code for Antipumping relay? ANSI codes 94 or even 52 can be used. Relays can be divided into six functional categories shown below: Detect defective lines, defective apparatus, or other dangerous or intolerable conditions. These relays generally… Read more
Jan 23, 2012 | By Asif Eqbal
UK Electrical Industry British Standards (BS)
These standards are the whole of the prescriptions on the basis of which machines, apparatus, materials and the installations should be designed, manufactured and tested so that efficiency and function safety are ensured – and all according to the UK Electrical… Read more
Jan 20, 2012 | By Edvard Csanyi
How lightning really works? (video)
A lightning discharge develops in three stages: first, the collisions between ice particles and water droplets together with gravity separate positive and negative charges inside the thunder cloud and buildup a voltage. Then a discharge grows, forming a so-called streamer-leader… Read more
Jan 17, 2012 | By Edvard Csanyi
What Is The Potential Difference?
Potential difference is the term used to describe how large the electrostatic force is between two charged objects. If a charged body is placed between two objects with a potential difference, the charged body will try to move in one direction, depending upon the polarity of the object. If… Read more
Jan 13, 2012 | By Edvard Csanyi
Effective Resistance Of Busbars
The construction of busbar is usually carried out by putting together several flat bars in parallel for each phase. The spacing between the bars is made equal to their thickness for practical reasons, and this leads to skin and proximity effects. If one refers to… Read more
Jan 12, 2012 | By Edvard Csanyi
Operation Of Potentially Explosive Installations – The Directive 99/92/EC
In addition to the 94/9/EC Directive, which regulates how explosion protected equipment and protective systems are placed on the market and the design, construction and quality requirements to be met by them, the 99/92/EC Directive stating “Minimum requirements for improving the health and safety protection… Read more
Jan 09, 2012 | By Edvard Csanyi
Voltage and Current Phase Relationships in an Inductive Circuit
Any change in current in a coil (either a rise or a fall) causes a corresponding change of the magnetic flux around the coil. Because the current changes at its maximum rate when it is going through its zero value… Read more
Jan 05, 2012 | By Edvard Csanyi
The Need for Breaker Failure Protection
Circuit breakers are strategically located in power systems to connect circuits and electrical apparatus. Circuit breakers are commanded to open and close by protection and control systems that monitor conditions on the power system. Protection systems are coordinated so that… Read more
Jan 01, 2012 | By Edvard Csanyi
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
What psychological effect does an electric shock?
Most of us have experienced some form of electric ”shock”, where electricity causes our body to experience pain or trauma. If we are fortunate, the extent of that experience is limited to tingles or jolts of pain from static electricity… Read more
Dec 25, 2011 | By Edvard Csanyi
What is HIPOT Testing (Dielectric Strength Test)?
Hipot Test is short name of high potential (high voltage) Test and it is also known as Dielectric Withstand Test. A hipot test checks for “good isolation”. Hipot test makes surety of no current will flow from one point to… Read more
Dec 22, 2011 | By Jignesh Parmar
Earthing in electrical network – purpose, methods and measurement
The main reason for doing earthing in electrical network is for the safety. When all metallic parts in electrical equipment are grounded then if the insulation inside the equipment fails there are no dangerous voltages present in the equipment case…. Read more
Dec 19, 2011 | By Jignesh Parmar
What is the resonance phenomena?
The use of both capacitive and inductive devices in distribution systems leads to resonance phenomena, resulting in extremely high or low impedance values. These variations in impedance modify the current and voltage in the distribution system. Here we will discuss… Read more
Dec 09, 2011 | By Edvard Csanyi
Flexible AC Transmission System – What and Why?
Flexible AC Transmission System (FACTS) have been evolving to a mature technology with high power rating. This technology has wide spread application, became a top rate, most reliable one, based on power electronics. The main purpose of these systems is… Read more
Dec 05, 2011 | By Edvard Csanyi
5 steps to choose the best motor for your application
For line-operated motors, loads fall into three general categories: constant torque, torque that changes abruptly, and torque that change gradually over time. Bulk material conveyors, extruders, positive displacement pumps, and compressors without air unloaders run at relatively steady levels of… Read more
Dec 03, 2011 | By Edvard Csanyi
