By A. Wright, C. Christopoulos
Electrical energy process Protection offers practicing engineers with the main up to date and finished one -volume reference and educational on energy method safety to be had. targeting primary tools and know-how and with huge examples drawn from present perform across the world, this publication should be a tremendous reference software for engineers concerned with and laid low with strength approach protection.
Read Online or Download Electrical Power System Protection PDF
Best electrical & electronics books
- The J & P Transformer Book A Practical Technology of the Power Transformer
- Mathematik für Ingenieure und Naturwissenschaftler: Ein Lehr- und Arbeitsbuch für das Grundstudium
Additional resources for Electrical Power System Protection
It must be realized that their operating times in suth circumstances will be longer than those obtained when operating at 50 Hz. As a result higher arc energies will be released in the fuse links, and to ensure that satisfactory clearance will be obtained, their ratings in terms of operating voltage may have to be lowered. s. Fig. 19 Fuse cut-off characteristics. c. applications the voltage rating must usually be reduced very significantly, particularly if the circuit is highly inductive. 7 Discrimination and coordination Most power circuits contain many items of equipment and these are both in series and parallel paths.
C. c. circuits up to 500 V. 1 and illustrated in Fig. 4. Such fuses are produced in large numbers and many are fitted in distribution fuse boards. Fuselinks with current ratings above about 200 A are large and produced in small quantities. They are normally installed directly in convenient positions without their own special or standardized housings. They are often incorporated in fuse-switch units, an example being shown in Fig. 13. c. systems operating at frequencies of 50 Hz and 60 Hz with rated voltages exceeding 1000 V.
At this time, current and voltage transformers could readily have been produced because of their basic similarity to power transformers and it seems probable that they were installed to feed measuring instruments associated with the high voltage circuits then in existence. Another matter of significance is that doubts were being expressed around the tum of the century about the use of fuses as protective devices, possibly because their manufacture was not adequately controlled. Apparently they were causing unnecessary interruptions of supplies to consumers.