Network harmonics analysis – Installation with 6-pulse rectifier, capacitors & filters
The diagram in figure 1 represents a simplified network comprising a 2,000 kVA six-pulse rectifier, injecting a harmonic current spectrum, and the following equipment which will be considered consecutively in three different calculations. So, let’s list these calculations and start with… Read more
Apr 21, 2017 | By Edvard Csanyi
Rules for dimensioning, disconnecting and protecting the neutral conductor
Dimensioning of neutral conductor Smaller than the cross-sectional area of the phase conductors… Equal to the cross-sectional area of the phase conductors Greater than or equal… Neutral conductor disconnection TN-C system TT or TN-S system IT system Important recommendations #1… Read more
Apr 19, 2017 | By Edvard Csanyi
Thumb rules for surge arrester installation in different earthing systems
A variety of documents deal with the subject of surge arrester installation: for example in France, standard NF C 15-531 focuses on the installation rules of LV surge arresters, and standard NF C 15-100 covers all the LV electrical installations…. Read more
Apr 17, 2017 | By Edvard Csanyi
Circuit breaker selections for low voltage installation (with discrimination)
The LV installation which forms the subject of this study is shown in figure 1 above. This study includes discrimination and coordination of protection between the LV equipment and the protection located upstream of each MV/LV power supply transformer. The… Read more
Apr 14, 2017 | By Edvard Csanyi
Six network operating conditions under which ferroresonance can occur
Due to the multitude of various sources of capacitances and non-linear inductances in a real power network and the wide range of operating conditions, configurations under which ferroresonance can occur are endless. Experience has, however, made it possible to list… Read more
Apr 12, 2017 | By Edvard Csanyi
8 essential relay operating principles of catching faults
In general, as faults (short circuits) occur, currents increase in magnitude, and voltages go down. Besides these magnitude changes of the AC quantities, other changes may occur in one or more of the following parameters: phase angles of current and… Read more
Apr 10, 2017 | By Edvard Csanyi
Three main techniques for mitigating step and touch potential hazards
Mitigating step and touch potential hazards is usually accomplished through one or more of the following three main techniques. Understanding the proper application of discussed techniques is the key to reducing and eliminating any ground potential rise hazards. Contents: Reduction… Read more
Apr 07, 2017 | By Edvard Csanyi
How good are you at reading electrical drawings? Take the quiz.
Every electrician, in every branch of electrical work, will need to consult and understand the information presented on electrical drawings to locate the various outlets, the routing of circuits, the location and size of panelboards, and other similar electrical details…. Read more
Apr 05, 2017 | By Edvard Csanyi
Two main functions of an earth electrode and its installation parameters
The prime function of an earth electrode is the protection of persons. That’s it. It is a fact that we live on Earth! And it is vital to earth exposed metal parts of electrical equipment to avoid electrocution by indirect… Read more
Apr 03, 2017 | By Edvard Csanyi
Wiring of power factor relay on LV and MV side (circuit diagrams)
In order to measure electrical power the relay needs to receive the line voltage and current from a current transformer (CT) installed close to the metering point, if possible. To measure reactive power at the power factor relay especially, it… Read more
Mar 31, 2017 | By Edvard Csanyi
Five protection relay types used to detect grid disturbances and isolating
Consider a medium voltage distribution system having local generation (e.g., captive power generation) as shown in figure 1 which is also synchronized with the grid. During grid disturbance, if plant generators are not successfully isolated from the grid, they also sink… Read more
Mar 29, 2017 | By Edvard Csanyi
Top six solutions to achieve a high level of energy efficiency in buildings
Energy efficiency in commercial buildings involves providing a given level of performance, cost, quality, availability, and comfort at a minimal level of energy usage throughout the lifecycle of a given asset or process. Generally speaking, energy efficiency involves reducing energy… Read more
Mar 27, 2017 | By Edvard Csanyi
The analysis of four network schemes in terms of reliability and protection
Before sizing an electric network, the single-line diagram of the electric network must be defined on the basis of: Load – it is considered fundamental to establish the true user and service requirements these are destined for, in terms of quality, availability… Read more
Mar 24, 2017 | By Edvard Csanyi
Generator synchronizing check protective function (ANSI 25 code)
One of the easiest way to damage a generator is to synchronize or parallel out of phase with the electrical system. Out-of-phase synchronizing operations can damage or reduce the remaining life of generator rotors and stationary components. Angular differences as… Read more
Mar 22, 2017 | By Edvard Csanyi
Installation, protection and connection of capacitor banks
In an low voltage electrical installation, capacitor banks can be installed at three different levels: Global installation Segment (or group) installation Individual (or single) installation After installation ways, we’ll discuss about protection and connection of capacitors banks. This installation type assumes… Read more
Mar 20, 2017 | By Edvard Csanyi
