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Over Current Relays working and explanation in simple way. By Yuvi - Study Point

Hey everyone, today we are going to learn about Overcurrent relays in a simple or easy way.
So, without wasting any time lets get started.

  • Against excessive currents over current protections protects electrical power. These excessive currents are caused by short circuits, ground faults, etc.
  • The over-current relay consists only one current operated element means there is no voltage coil etc is required to construct this protective relay.
  • As I have already said that, in an overcurrent relay the actuating quantity is only current.
  • There would be essentially a current coil in an overcurrent relay.
  • When a normal current flows through this current coil, then the magnetic effect generates by the coil which is not sufficient to move the moving element of the relay.
  • And in this condition, the restraining force is greater than the deflecting force.
  • But when the current through the coil increases, then the magnetic effect also increases and after a certain level or value of current, the deflecting torque which is produced by the magnetic effect of the coil crosses the restraining force.
  • Then the moving element of the relay starts moving and changes the contact position in the relay.     
There are different types of Overcurrent relays ~
  • Instantaneous Overcurrent Relay
  • Definite Time Overcurrent Relay
  • Inverse Time Overcurrent Relay
Inverse time overcurrent relay is further subdivided~
  1. (IDMT) Inverse Definite Minimum Time Overcurrent Relay
  2. Very Inverse Time Overcurrent Relay
  3. Extremely Inverse Time Overcurrent Relay
                    

https://youtu.be/LyX6805PmMg

{ In this lecture video I have given a simple explanation about the overcurrent relay, its working principle, its types, etc.
So, please go and check out my channel and this video. }

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