• Switchboards and motor control centre name and tag number. • Bus-section numbers or letters. • Cubicle numbers or letters. • Line voltage, number of phases, number of wires, frequency, busbar continuous current rating. • Busbar nominal fault breaking capacity in kA at 1 or 3 seconds. • Identification of
Year: 2013
Single-line diagrams are the most essential documents that are developed during the detail design phase of a project. They identify almost all the main items of power equipment and their associated ancillaries. Initially they define the starting point of a project. Finally they are a concise record of the design,
The rating of a motor should exceed that of its driven machine by a suitable margin. The selection of this margin is often made by the manufacturer of the driven machine, unless advised otherwise. The actual choice depends on various factors e.g. Approximate rating of the motor or machine (kW)
Some basic and important points, in relation to a modern power system, are summarized below: 1. Generation, transmission and distribution of electric power in our country is carried out as 3-phase system at 50 Hz. 2. Three most important conventional methods of power generation in out country are: coal based
Nuclear power plants are thought to be the solution for bulk power generation. The present day atomic power plants work on the principle of nuclear fission of 235U. In the natural uranium, 235U constitutes only 0.72% and remaining parts is constituted by 99.27% of 238U and only about 0.05% of
In a hydral power station, water head is used to drive water turbine coupled to the generator. Water head may be available in hilly region naturally in the form of water reservoir (lakes etc.) at the hill tops. The potential energy of water can be used to drive the turbo
In a thermal power station coal is burnt to produce steam which in turn, drives the steam turbine hence the generator (turbo set). In figure the elementary features of a thermal power plant is shown. In a thermal power plant coil is burnt to produce high temperature and high pressure
A.C power can be generated as a single phase or as a balanced poly-phase system. However, it was found that 3-phase power generation at 50 Hz will be economical and most suitable. Present day three phase generators, used to generate 3-phase power are called alternators (synchronous generators). An alternator has
For switchboards other than those for the generator or intake feeders it is established practice toadd some margin in power capacity of their feeders so that some future growth can be accommodated.The margin is often chosen to be 25% above the TPPL. If the feeders are plain cables or overhead
Heavy industrial gas turbines are usually to be found in refineries, chemical plants and power utilities. They are chosen mainly because of their long and reliable running times between major maintenance overhauls. They are also capable of burning most types of liquid and gaseous fuel, even the heavier crude oils.
