What Is the Skin Effect?
the skin effect is where Ac current tends to avoid travel through the center of a solid conductor, limiting itself to conduction near the surface.
لماذا تصنع الكابلات الكهربية من مجموعة من الاسلاك الملفوفه حول بعضها ؟؟
يفضل في صناعة الكابلات تقسيم مساحة مقطع الموصل الي مجوعة من الموصلات ذات مساحة مقطع اقل ،علي الرغم من ان ذلك يتطلب مجهودا اكبر في عملية الصناعة ، كل ذلك للتقليل من الظاهرة السطحية للتيار المتردد .
Some Benefits of Fiber Optics vs. Copper cable:
•Low loss of signal .
•Large data-carrying capacity .
•Greater resistance to electromagnetic noise .
•No electromagnetic radiation
•safe to use near high-voltage equip
•Low weight
•No crosstalk between cables
Fiber Optic cable “ Optical Fiber cable “ ::
1- What is Fiber optic ? FOC !
2- How does Optical Fiber Work?
3- Construction of Fiber ?
4- Fiber Types ? and benefits of FOC ?
The voltage of a circuit is designated in accordance with the following principles:
Example:
Uo/U (Um) : 130/225 (245)
Uo = 130 kV phase-to-ground voltage,
U = 225 kV rated phase-to-phase voltage,
Um = 245 kV highest permissible voltage of the grid
It is placed in both the high and low voltage side of the power transformer. It is used for de-energizing the equipment for testing and maintenance and for clearing the fault.