Energy and Power
Arrangements of LV Utility Distribution Networks
In European countries the standard 3-phase 4-wire distribution voltage level is 230/400 V. Many countries are currently converting their LV systems to the latest IEC standard of 230/400 V nominal (IEC 60038). Medium to large-sized towns and cities have underground… Read more
Nov 30, 2012 | By Edvard Csanyi
Protection
The Purpose Of Transformer Gas Relay
The transformer gas relay is a protective device installed on the top of oil-filled transformers. It performs two functions. It detects the slow accumulation of gases, providing an alarm after a given amount of gas has been collected. Also, it… Read more
Nov 29, 2012 | By Edvard Csanyi
Energy and Power
How to Predict Life Span of the Switchgear?
The life span of switchgear basically depends on the size of the load and the number of switching cycles. Instead of a time span, with electromechanical switchgear reference is usually made to the number of operations, as the ageing mainly… Read more
Nov 28, 2012 | By Edvard Csanyi
Cables
Inspection and Test Procedures for LV Cables
Visual and Mechanical Inspection Electrical Tests Test Values TABLE 100.12 – US Standard Fasteners – Bolt-Torque Values for Electrical Connections Compare cable data with drawings and specifications. Inspect exposed sections of cables for physical damage and correct connection in accordance with… Read more
Nov 27, 2012 | By Edvard Csanyi
Protection
Surge Protection for Frequency Converters
In principle a frequency converter consists of a rectifier, a d.c. link converter, an inverter and of the control electronics (Figure 1 above). At the input of the inverter the single phase or interlinked, three-phase a.c. voltage is changed into a… Read more
Nov 26, 2012 | By Edvard Csanyi
Energy and Power
Purpose of Miniature Circuit Breakers (MCBs)
Miniature circuit breakers (MCB) are primarily designed to protect cables and lines against overload (thermal) and short-circuit (electromagnetic). They thus care for protecting this electrical equipment against excessive temperature rises and destruction in the event of a short-circuit. They meet the requirements… Read more
Nov 24, 2012 | By Edvard Csanyi
High Voltage
HV Instrument Current Transformers in T&D
Electrical measurements on a high-voltage transmission and distribution systems cannot be made practically or safely with direct contact to the power carrying conductors. Instead, the voltages and currents must be brought down to a safe and usable level that can… Read more
Nov 23, 2012 | By Edvard Csanyi
Variable Speed Drives
VLT Drives in Wastewater Treatment Plant Applications
The most common use of frequency converters is to drive sludge pumps, elevators, conveyers, aeration, chemical dosing, clarifiers, digesters, presses and centrifugal dewatering. In the beginning water is being pumped into the plant from the collection basin. The frequency converter… Read more
Nov 22, 2012 | By MarkoCvrkota
Industrial Automation
Few Words About Frequency Converters
Since the late 1960’s, frequency converters have undergone extremely rapid changes, largely as a result of the development of microprocessor and semi-conductor technologies and their reduction in prices. However, the basic principles of frequency converters remains the same. Frequency converters can be divided into… Read more
Nov 21, 2012 | By Edvard Csanyi
Wind Power
Wind power applications, Grid connected or not?
There are perhaps four distinct categories of wind power which should be discussed. These are: Small, non-grid connected Small, grid connected Large, non-grid connected Large, grid connected By small, we mean a size appropriate for an individual to own, up… Read more
Nov 20, 2012 | By Edvard Csanyi
Electric Motor
Stator Overheating Protection
All motors need protection against overheating resulting from overload, stalled rotor, or unbalanced stator currents. For complete protection, three-phase motors should have an overload element in each phase. This is because an open circuit in the supply to the power… Read more
Nov 19, 2012 | By Edvard Csanyi
Industrial Automation
How to Select Right Frequency Converter for Variable Speed Drive (VSD)?
Selecting of a frequency converter for variable speed drives requires a lot of experience. If the experience is not available, it is often useful to visit either a reference plant with similar applications, or exhibitions or trade shows. The following is a… Read more
Nov 17, 2012 | By Edvard Csanyi
High Voltage
The Purpose of High Voltage Circuit Switchers
Circuit switchers have been developed to overcome some of the limitations of fusing for substation power transformers. Circuit switchers have SF6 gas interrupters and are designed to provide three-phase interruption (solving the unbalanced voltage considerations) and to provide protection for… Read more
Nov 16, 2012 | By Edvard Csanyi
Energy and Power
What’s common for Beer Mug and Power Factor?
Understanding power factor is not that hard. We have some very common example from the real life you will understand for sure, but first let’s start with some introduction of power factor. To understand power factor, we’ll first start with… Read more
Nov 15, 2012 | By Edvard Csanyi
High Voltage
Electrical Safety Standards for LV/MV/HV (Part-3)
Continued from part 2 – Electrical Safety Standards for LV/MV/HV (Part-2) Standard: Northern Ireland Electricity (NIE), 6/025 ENA Code: Indian Electricity Rules / Central Electricity Authority Right of Way Clearance (As per GETCO Standard) Minimum clearances between Electrical Lines crossing… Read more
Nov 14, 2012 | By Jignesh Parmar
