If r is the radius of the conductor and R the radius of the sheath of the cable, the cable operates stably from the view point of dielectric strength if:
The cable operates stably from the view point of dielectric strength if,
The insulation resistance of a cable of 10 km length is 1 MΩ. The resistance for a length of 40 km is
It seems amazing that Insulation Resistance (IR) of a Cable is inversely proportional to the length of Cable. As per our general perception, the resistance is directly proportional to length of conductor but mind here that it is not the resistance of conductor rather it is the resistance of the Insulation provided around the conductor.
The insulation resistance of a cable,
Ri2 = 0.25 MΩ
Sheath losses can be eliminated by
Armouring protect cables against
Match List-l (Type of Cables) with List-ll (Operatng Voltages) and select the correct answer using the code given below the lists:
Consider the following statements:
1. AAC (All Aluminium conductors) are universaly employed for feeders as well as distributors.
2. The conductor size for a feeder is mainly governed by the permissible voltage drop in the line.
Which of the above statement(s) is/are true?
ACSR conductors are universally employed for distribution systems (feeders as well as distributors), AAC can be used for distribution purpose provided the spans are small.
Hence, statement-1 is false.
The conductor size for a feeder is mainly governed by current carrying capacity and overall economy. Hence, 2 is also a false statement.
Which of the following distribution systems is the most economical?
For high voltage transmission lines, conductors are suspended from towers so as to
The function of steel wire in an ACSR conductor is to
The string efficiency of insulators can be increased by