If the number of poles in a 3-ϕ 11 kV transmission line is 80, then how many disc insulators are required?

This question was previously asked in
SSC JE EE Previous Year Paper 15 (Held On: 26 Sep 2019 Evening)
View all SSC JE EE Papers >
  1. 240
  2. 80
  3. 6
  4. 160

Answer (Detailed Solution Below)

Option 1 : 240
Free
RRB JE CBT I Full Test - 23
14.2 K Users
100 Questions 100 Marks 90 Mins

Detailed Solution

Download Solution PDF
  • In suspension insulator number of insulators is connected in series to form a string and the line conductor is carried by the bottom-most insulator.
  • Each insulator of a suspension string is called a disc insulator because of its disc-like shape.
  • Each suspension disc is designed for a normal voltage rating of 11 kV, so by using different numbers of discs, a suspension string can be made suitable for any voltage level.

As the rating of each disc insulator is 11 kV, for an 11 kV transmission line the disc insulator required at each pole is 1.

Therefore, the total number of insulators used in a transmission line having 80 poles is = 1 × 80 = 80

For three phases, the total number of disks required = 80 × 3 = 240

Latest SSC JE EE Updates

Last updated on May 29, 2025

-> SSC JE Electrical 2025 Notification will be released on June 30 for the post of Junior Engineer Electrical/ Electrical & Mechanical.

-> Applicants can fill out the SSC JE application form 2025 for Electrical Engineering from June 30 to July 21.

-> SSC JE EE 2025 paper 1 exam will be conducted from October 27 to 31. 

-> Candidates with a degree/diploma in engineering are eligible for this post.

-> The selection process includes Paper I and Paper II online exams, followed by document verification.

-> Prepare for the exam using SSC JE EE Previous Year Papers.

More Transmission and Distribution Questions

Get Free Access Now
Hot Links: teen patti master official teen patti lucky teen patti master update teen patti casino download