What is the purpose of incorporating intersheaths in cables_____________?
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Answer: C. provide proper stress distribution
Explanation
Intersheaths are conductive metallic layers placed at intervals within thick cable insulation systems. They ensure proper electrostatic stress distribution across the multiple layers of cable dielectric. Dividing the total voltage stress prevents localized insulation breakdown in thick high voltage cables. Electrostatic stress in cable insulation is highest near the inner conductor and lowest outward. Graded cables use multiple insulation layers with intersheaths connected to intermediate potentials. Proper stress distribution maximizes the utilization of the dielectric material strength.
High voltage direct current and alternating current cables utilize grading techniques for safety. Power engineers design graded insulation to reduce the overall diameter and cost of cables. Effective stress management prevents premature insulation failure in high voltage underground networks. Minimizing stress is achieved as a direct result of providing proper stress distribution. Intersheaths do not eliminate the requirement for using high quality insulating materials. Options suggesting none of the above overlook the established engineering purpose of intersheaths.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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