(Solved) The capacitor connected in parallel with an equipment provides some degree of protection against

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Question :

The capacitor connected in parallel with an equipment provides some degree of protection against... (GETCO 2012) 

A. Neutral displacement

B. Ferranti effect 

C. Loss of stability 

D. Surges


Answer : D

Explanation :

  •  Before the surge can impress a high voltage on the equipment, it must charge the capacitor. 
  • By temporary energy storage in them, the modifiers reduce the steepness of the surge wave front, which otherwise can be damaging to apparatus, since the voltage across the equipment can rise only as quickly as the capacitor can be charged through the line. 
  • Capacitors are particularly effective against short duration surges. 
  • The energy of these surges is such that it can be absorbed by the capacitors. 
  • However, for high energy surges, the size and cost of capacitors becomes prohibitive. 
  • The combination of a capacitor and an arrester can be very useful because they complement each other. The capacitor reduces the steepness of the wave. 

  • A reactor connected in series with the equipment also serves an identical purpose. When a surge reaches the reactor, it initially appears only across the reactor, the reactor offers high impedance to the high frequency currents. The surge energy is initially absorbed in the magnetic field of current in the reactor. Its ability to store energy is limited but it can take care of low energy surges.

Hope this explanation will help you to solve your queries. Please comment below for further queries. Thank you! 

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