Bissoy.com
Doctors Medicines MCQs Q&A

Which of the following is NOT one of the causes of insulator failure?

Which of the following is NOT one of the causes of insulator failure? Correct Answer Insulator glazing

Causes of Insulator Failure: There are different causes due to which failure of insulation in the electrical power systems may occur:

Cracking of Insulator:

  • The porcelain insulator mainly consists of three different materials.
  • The main porcelain body, steel fitting arrangement, and cement to fix the steel part with porcelain.
  • Due to changing climate conditions, these different materials in the insulator expand and contract at different rates.
  • These unequal expansion and contraction of porcelain, steel, and cement are the chief cause of the cracking of insulators.
     

Porosity in The Insulation Materials:  If the porcelain insulator is manufactured at low temperatures, it will make it porous, and due to this reason it will absorb moisture from air thus its insulation will decrease and leakage current will start to flow through the insulator which will lead to insulator failure.

Flash Over Across Insulator: If a flashover occurs, the insulator may be overheated which may ultimately result in shuttering of it.

Mechanical Stresses on Insulator:

  • If an insulator has any weak portion due to a manufacturing defect, it may break from that weak portion when mechanical stress is applied to it by its conductor.
  • These are the main causes of insulator failure. Now we will discuss the different insulator test procedures to ensure the minimum chance of failure of insulation.
     

Note: Glazing on ceramic insulators is done to make it smooth and non-absorbent.

Related Questions

Each material circumstance appearing in evidence against the accused must be put to the accused specifically, distinctly and separately. In this context, the propositions are
1. Failure to put the material evidence to the accused always vitiates the trial
2. Failure to put the material evidence amounts to a serious irregularity which can not be cured and vitiates the trial, if it has prejudiced the accused.
3. Failure to put the material evidence is not considered to services & is curable if infact no failure of justice has occasioned to the accused.
Now which of the following is correct
Consider the following statements regarding typical analysis of bolt failure :  1. 15% failure of bolt occur at the fillet under the head. 2. 50% failure of bolt occur at the end of threads on the shank. 3. 80% failure of bolt occur in the threads that are in contact with the nut. Which of the above statements is/are correct ?
Consider the following statements associated with local shear failure of soils: 1. Failure is sudden with well-defined ultimate load. 2. This failure occurs in highly compressible soils. 3. Failure is preceded by large settlement. Which of these statements are correct ?
The variance of failure time (time to failure) of an electric motor in shovel is 1600 hr2. If the failure time follows an exponential distribution. the expected mean time between failure in hr is
A dielectric is always an insulator. But an insulator is not necessarily a dielectric. State True/False.
The following pie chart represents the number of 455 large oil tanker accidents due to various causes of spillage during a 20-year period.Study the pie chart and answer the following question. If the sum of the number of tanker accidents due to fire and unknown causes is 180, then what is the difference between the number of tanker accidents due to hull failure and equipment failure?
Which of the following insulator is similar to pin type insulator?
Consider a three-phase. 50 Hz, 11 kV distribution system, Each of the conductors is suspended by an insulator string having two identical porcelain insulators. The self-capacitance of the insulator is 5 times the shunt capacitance between the link and the ground, as shown in the figure. The voltage across the two insulators are
A designer wanted to design the insulator for the underground cable, then the estimation of thickness of the insulator will depend on ______________
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Dyslexia is a perceptual disorder often occurring in persons of normal, or even above average intelligence. The reader is unable to perceive correctly what is on a page. Letters and numbers often appear reversed: "b" seems to be "d","quite" is "quiet" and "from" is "form". The reader tends to leave out letters or words or insert words or letters that are not there. Vowel and consonant sounds may be confused. Many dyslexics are left­handed or able to write with either hand. They often confuse left and right. Learning to speak may also be delayed beyond infancy. The condition seems to be inherited. It may persist into adulthood. However, with early recognition and specialized approaches to teaching reading, most dyslexics can learn to read. Some researchers believe that latent dyslexia may be aggravated by the way reading is taught. The modern whole­word, or look­and­say, method seems to be more of a hindrance to learning for dyslexics than it is for ordinary pupils. The phonetic method of teaching students to learn letters and sound them out appears to achieve better reading results. The problem of words that cannot be sounded out ­ such as rough, laugh or through ­ is not solved by phonetics. These words must simply be memorized. However, for children with dyslexia the problem can be compounded by the failure of parents or teachers to recognize the condition. This can easily lead to emotional problems for dyslexic children, who cannot understand their failure to keep up with their classmates.
The problem of perception can be compounded by the failure of parents and teachers to