Cables
Underfloor cable systems explained in details
It should be understood that the generic term ‘underfloor’ applies to products designed for such use but which may well be used in other environments where the protection is appropriate. Ducts and risers, and within suspended ceilings are typical spaces… Read more
Mar 24, 2014 | By Edvard Csanyi
Energy and Power
Electrical Design Project of a Three Bed Room House (1)
Electrical design is not an easy task. It requires a lot of expertise. Detailed study is needed prior to installation work. The engineer must consider quality and any specific requirements together with price. Different options are to be examined. Choice… Read more
Mar 21, 2014 | By Sufi Shah Hamid Jalali
High Voltage
Hey Mom, look at that big HVDC Transformer!
HVDC transformers are key components of HVDC stations. HVDC converter and inverter stations terminate long-distance DC transmission lines or DC sea cables. This type of transformer provides the interface between AC grids and high power rectifiers and are used to… Read more
Mar 19, 2014 | By Edvard Csanyi
Industrial Automation
Let’s start learning the PLC programming
For managing and control of the electrical systems there once were used electromechanical relays. In time as technology advanced came and PLC devices (Programable Logics Controllers). Advantage of an PLC devices over relays is that they can be used for a… Read more
Mar 17, 2014 | By Vlada Markovic
Power Substation
How To Locate Current Transformers in HV Substation
Current transformers are used for protection, instrumentation, metering and control. It is only the first function that has any bearing on the location of the current transformer. Ideally the current transformers should be on the power source side of the circuit… Read more
Mar 14, 2014 | By Edvard Csanyi
Testing and Commissioning
Testing of power transformer – Measurement of impedance voltage and load loss
The measurement is carried out to determine the load-losses of the transformer and the impedanse voltage at rated frequency and rated current. On Figure 1 above (Circuit for the impedance and load-loss measurement) there are following figures: G1 – Supply… Read more
Mar 12, 2014 | By Edvard Csanyi
Energy and Power
Electrical Thumb Rules You MUST Follow (8)
Accuracy Class of Metering CT Accuracy Class Letter of CT Accuracy Class of Protection CT Continued from part 7: Electrical Thumb Rules You MUST Follow (Part 7) Metering Class CT Class Applications 0.1 To 0.2 Precision measurements 0.5 High grade… Read more
Mar 10, 2014 | By Jignesh Parmar
Electric Motor
Motor Starting via Chokes or Resistors
The series-connected chokes (Figure 1) or resistors (Figure 2) reduce the voltage at the motor and hence also the starting current. The starting torque is reduced by around the square of the current. At rest the motor impedance is small…. Read more
Mar 07, 2014 | By Edvard Csanyi
Energy and Power
The Risk Of Deadly Lightning Current and Few Things You Should Know
Lightning currents are load-independent currents, i.e. a lightning discharge can be considered an almost ideal current source. If a load-independent active electric current flows through conductive components, the amplitude of the current, and the impedance of the conductive component the current flows… Read more
Mar 05, 2014 | By Edvard Csanyi
Energy and Power
Total Losses in Power Distribution and Transmission Lines (2)
Continued from first part: Total Losses in Power Distribution & Transmission Lines (1) There are two types of transmission and distribution losses: Technical losses (explained in previous part) Non-technical losses (commercial losses) Non-technical losses are at 16.6%, and related to… Read more
Mar 03, 2014 | By Jignesh Parmar
Testing and Commissioning
Testing Procedures for HV Voltage Transformers
Equipment required for testing General inspection Insulation Resistance Test Polarity Test Transformer Turns ratio test Following equipment is necessary to perform testings: Polarity test kit Megger 500-5000V Ohmmeter Multimeter Autotransformers & Step-up transformers Go up to the Content General visual… Read more
Feb 28, 2014 | By Edvard Csanyi
Cables
Practices for grounding and bonding of cable trays
Cable tray may be used as the Equipment Grounding Conductor (EGC) in any installation where qualified persons will service the installed cable tray system. There is no restriction as to where the cable tray system is installed. The metal in… Read more
Feb 26, 2014 | By Edvard Csanyi
Electric Motor
Inspection and test procedures for Rotating Machinery, Synchronous Motors and Generators
Visual and Mechanical Inspection Electrical Tests Test Values Visual and Mechanical Tests Electrical Tests Pictures: Electrical machine wired for electrical testing The Electrical Machines Laboratory TABLE 100.10 – Maximum Allowable Vibration Amplitude TABLE 100.12 – US Standard Fasteners Compare equipment… Read more
Feb 19, 2014 | By Edvard Csanyi
Transformers
How challenging can be transporting of a Large Power Transformer (LPT)
Transporting an Large power transformer (LPT) can be quite challenging. LPTs large dimensions and heavy weight pose unique requirements to ensure safe and efficient transportation. Current road, rail, and port conditions are such that transportation is taking more time and… Read more
Feb 14, 2014 | By Edvard Csanyi
Energy and Power
Effect of utility-induced surges in a steel mill with variable speed drives
A steel mill with variable speed drives (VSDs) had problems of frequent tripping of the VSDs with the indication overvoltage in AC line. Each tripping caused severe production disruption and resulted in considerable monetary loss due to lost production. Steady-state… Read more
Feb 12, 2014 | By Edvard Csanyi
