Maintenance
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… Read more
May 12, 2014 | By jiguparmar
Energy and Power
Electromagnetic stresses on a busbar system and methods of reducing
When a conductor carries a current it creates a magnetic field which interacts with any other magnetic field present to produce a force. When the currents flowing in two adjacent… Read more
Apr 02, 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… Read more
Feb 19, 2014 | By Edvard Csanyi
Electrical Lectures
What is the short-circuit switching (making / breaking) capacity?
The switching capacity is the r.m.s value of a current at a given power factor cos φ as well as a given rated voltage at which a switchgear or a… Read more
Feb 10, 2014 | By Edvard Csanyi
Technical Guide/Paper
Technical considerations in the specification and design of low voltage switchboards
Cubicles may be front access only, rear access only or front and rear access. This has clear ramifications with regard to cable accommodation and access. What should not be overlooked… Read more
Jan 10, 2014 | By Edvard Csanyi
Electrical Lectures
Important in role of capacitors in distribution systems
Should the voltage on a circuit fall below a specified level for some reason, a device called a capacitor can momentarily maintain the voltage at line value. Basically, a capacitor… Read more
Nov 27, 2013 | By Edvard Csanyi
Electric Motor
Identity Card of Every Asynchronous Motor
A motor is characterized by different electrical and constructional parameters which identify its correct application field. The whole of all these parameters constitutes the rating of the machine and is… Read more
Nov 18, 2013 | By Edvard Csanyi
Transmission and Distribution
The Need for Load Shedding In Generating, Transmission and Distribution Systems
The need for load shedding generally arises from unforeseen causes, lack of sufficient power supply from deficiencies in generating, transmission and distribution capabilities. These conditions may stem from unusually higher… Read more
Nov 11, 2013 | By Edvard Csanyi
Technical Guide/Paper
Load Listing, Calculations and Generator Sizing Spreadsheet
This calculator is commonly used for load listing, load calculations and generator size selection. Ratio between Absorbed Power and Rated Power Load Factor Motors between: 0kW – 15 kW 0.7… Read more
Nov 09, 2013 | By Edvard Csanyi
Medium Voltage
Field Inspection and Testing of Medium-Voltage Motor Control Centres (MCCs)
Check MCC equipment for: alignment, levelness, and tightness of all bolting. Check all equipment for: removal of blocking, supports, temporary ties, and temporary wire jumpers. Check that all protective barriers… Read more
Oct 28, 2013 | By Edvard Csanyi
Electric Motor
Sizing The DOL Motor Starter Parts (Contactor, Fuse, Circuit Breaker and Thermal Overload Relay)
Calculate size of each part of DOL motor starter for the system voltage 415V, 5HP three phase house hold application induction motor, code A, motor efficiency 80%, motor RPM 750,… Read more
Sep 11, 2013 | By jiguparmar
Electrical Lectures
Electrical Thumb Rules You MUST Follow (3)
Continued from second part: Electrical Thumb Rules You MUST Follow (Part 2) For Motor Size of Capacitor = 1/3 Hp of Motor ( 0.12x KW of Motor) For Transformer <… Read more
Sep 02, 2013 | By jiguparmar
Electric Motor
Drive Design in Electric Vehicles
Good Evening all, in this session I’m going to present some of the issues in drive design in the field of Electric Vehicle. I’ve organized the whole series into modules… Read more
Aug 21, 2013 | By Vishy
High Voltage
Talking about HV shunt reactor switching (1)
These notes aim to give basic idea of the main criticalities related to HV shunt reactor switching, particularly in terms of voltage, and how such problems are faced and solved… Read more
Jul 29, 2013 | By Nicola
Energy and Power
How to calculate voltage regulation of distribution line
Introduction to voltage regulation Voltage Regulation for 11KV, 22KV, 33KV Overhead Line Permissible Voltage Regulation (As per REC) Voltage Regulation Values Required Size of Capacitor Optimum location of capacitors Voltage… Read more
Jun 10, 2013 | By jiguparmar
