Arriving at the scene of a pole fire. What to do?
Utility pole fires are common and should be treated with great respect by firefighters. Pole fires are normally caused by the failure of insulators, switches, catastrophic failure of transformers or oil-filled switching equipment. Some poles used in the utility industry… Read more
May 21, 2014 | By Edvard Csanyi
Instrument transformers (CTs, VTs) in the system
The three main tasks of instrument transformers are: To transform currents or voltages from a usually high value to a value easy to handle for relays and instruments. To insulate the metering circuit from the primary high voltage system. To provide… Read more
May 19, 2014 | By Edvard Csanyi
The most common accessories you can find on oil filled transformer
Every oil filled transformer has a variety of accessories for different purposes. Here, I’ll try to name the most common of them, together with picture and description. Note that pictures can be different depending on manufacturer. Also, you will notice… Read more
May 16, 2014 | By Edvard Csanyi
Case study – Improper grounding practice of computers in buildings
In a large office complex, computer errors including system crashes/reboots were happening during thunderstorms. The grounding of computer system had been carried out according to the recommendations of manufacturers. The grounding leads were insulated and terminated to an isolated grounding bus. This bus… Read more
May 14, 2014 | By Edvard Csanyi
An example of calculating transformer size and voltage drop due to starting of large motor
Let’s calculate voltage drop in transformer 1000KVA, 11/0.480 kV, impedance 5.75% due to starting of 300 kW, 460V, 0.8 power factor, motor code D (kva/hp). Motor starts 2 times per hour and the allowable voltage drop at transformer secondary terminal is… Read more
May 12, 2014 | By Jignesh Parmar
Effects of Speed Variation on Rotodynamic Pumps
A rotodynamic pump is a dynamic device with the head generated by a rotating impeller. Thus, there is a relationship between impeller peripheral velocity and generated head. Peripheral velocity is directly related to shaft rotational speed, for a fixed impeller… Read more
May 09, 2014 | By Edvard Csanyi
10 Strategies for Automation and Production Systems
Following the USA Principle is a good first step in any automation project. The USA Principle is a common sense approach to automation projects. Similar procedures have been suggested in the manufacturing and automation trade literature, but none has a… Read more
May 07, 2014 | By Edvard Csanyi
Earthing (grounding) transformer – Voltages during a ground fault
Earthing Transformer or grounding transformer is the neutral grounding transformer – star connected on the primary and has an open delta on secondary. Open Delta has two terminals. A resistor is connected across these two terminals. Whenever a fault occurs, voltage… Read more
May 05, 2014 | By Asif Eqbal
9 typical issues addressed in a T&D network planning project
Transmission and distribution network planning projects are highly individual, because in each case the special conditions of the supply area, load demand and geographic distribution, technical standards and requirements, current status of the existing system, etc., have to be considered…. Read more
May 02, 2014 | By Edvard Csanyi
What affects the operating temperature within LV switchgear
BS EN 60439 states a maximum indoor ambient temperature of 40ºC, a maximum daily average of 35ºC and a minimum ambient of -5ºC. As a general guidance rule, the temperature within the low voltage switchgear should not exceed 50/55ºC. If… Read more
Apr 30, 2014 | By Edvard Csanyi
Purpose and Working Principle of Inductive Sensors
Inductive sensors use currents induced by magnetic fields to detect nearby metal objects. The inductive sensor uses a coil (an inductor) to generate a high frequency magnetic field as shown in Figure 1 below. If there is a metal object… Read more
Apr 28, 2014 | By Edvard Csanyi
An example of calculating the technical losses of T&D lines
There are two types of losses in transmission and distribution line. Technical Losses and Commercial Losses. It’s necessary to calculate technical and commercial losses. Normally technical losses and commercial losses are calculated separately. Technical losses of the distribution line mostly… Read more
Apr 25, 2014 | By Jignesh Parmar
How Best to Spend $450 Billion on Power Grid
Today’s power grid is suffering from a backlog in capital investment. While electrical power demand surged over recent years, electrical industry restructuring left utilities in a state of suspended animation. It is unclear who is responsible to make sure power… Read more
Apr 23, 2014 | By Edvard Csanyi
Offshore Floating Wind Turbines to Reap Green Electricity
In present day world, wind power has become one of the rapidly growing energy resources and have even become challenging to the other conventional resources and now have become more quieter and efficient too. A revolutionary change in the wind… Read more
Apr 21, 2014 | By sajna soman
5 technologies to boost efficiency in the T&D system
One example of efficiency measures aimed primarily at the utilities that operate the T&D system is an initiative underway at the US Department of Energy to implement new efficiency standards for distribution transformers. These are the grey cylinders you see… Read more
Apr 18, 2014 | By Edvard Csanyi
