What is the difference between a Circuit breaker and a relay?

Replies

• 

  grsalvi

  Assuming you know basic of switch gear components i answer below:
  
  1. Relay-"it is the sensing device which is connected to power circuit and if the any parameter of circuit crosses safe limits ,it sends signal to circuit breaker to break circuit."
  2. Circuit breaker-" A part of switchgear which is connected in circuit and it opens the circuit on receiving signal from relays"
  
  
  So,relays do only the sensing part and makes circuit breaker open its contacts to break the circuit.
  
  In case of very small application people might use relays to do both sensing and breaking circuit but mostly they are different as explained above.
  
  Ask if not clear.😀
• 

  kiransabarish

  grsalvi

  Assuming you know basic of switch gear components i answer below:
  
  1. Relay-"it is the sensing device which is connected to power circuit and if the any parameter of circuit crosses safe limits ,it sends signal to circuit breaker to break circuit."
  2. Circuit breaker-" A part of switchgear which is connected in circuit and it opens the circuit on receiving signal from relays"
  
  
  So,relays do only the sensing part and makes circuit breaker open its contacts to break the circuit.
  
  In case of very small application people might use relays to do both sensing and breaking circuit but mostly they are different as explained above.
  
  Ask if not clear.😀

  Thank you!!!
• 

  arunchary

  Relay is acts as a electromechanical switch it is not been used protection circuits,but circuit breakers are specially designed for circuit monitoring if any shot circuited then it breaks the main supply to follow towards load.but not in the case of relays.
• 

  arunchary

  you can follow the link for better understand.
  #-Link-Snipped-#
• 

  grsalvi

  I would add: More types of relays : electromechanical , numerical ,micro controller based
• 

  arunchary

  microcontroller based means .i think u r controlling relays using UC..
• 

  naveee

  A circuit breaker is a device for the limiting of current supplied to a circuit. Typically using a bi-metalic strip of metal to sense an increased current. The bi-metallic element will react to the increased current by heating up, and typically 'tripping' a mechanisim that will open or clear the circuit. When the bi-metallic unit cools of, the circuit breaker can usually be reset. After repeated 'trips', it is possible for the circuit breaker to become ineffective, wear out, and require replacement.
  A relay is an electro-mechanical device, typically used to control a system or application. Where as a electrical current is passed through a coil of wire, generating a magentic force which then effects a mechanical response. Such as opening or closing a contact that completes another electrical circuit.
  A circuit breaker is to designed to protect an electrical circuit, and a relay is designed to control one. Unless a relay has a circuit breaker included in the construction (very uncommon/extremely rare), it is no protection to an electrial device
• 

  arunchary

  yes exactly i was all ready read this topic ...my pal...
• 

  grsalvi

  arunchary

  microcontroller based means .i think u r controlling relays using UC..

  Micro controller based relays sense circuit through sensors and ADCs.
  They work on digital values representing the parameters of circuit.
  You can program micro controller as per your choice and hence provide protection the way you want.This provides flexibility and a single relay can detect two or more different parameters like current,power direction,temperature ,etc. In conventional relays you need different relays for different parameters.
• 

  Henri

  the mos
  

  grsalvi

  Assuming you know basic of switch gear components i answer below:
  
  1. Relay-"it is the sensing device which is connected to power circuit and if the any parameter of circuit crosses safe limits ,it sends signal to circuit breaker to break circuit."
  2. Circuit breaker-" A part of switchgear which is connected in circuit and it opens the circuit on receiving signal from relays"
  
  
  So,relays do only the sensing part and makes circuit breaker open its contacts to break the circuit.
  
  In case of very small application people might use relays to do both sensing and breaking circuit but mostly they are different as explained above.
  
  Ask if not clear.😀

  the most accurate answer by so far...
  i agree
• 

  Chirag jiwani

  Ya......it's perfect answer....
  

  Henri

  the mos
  
  the most accurate answer by so far...
  i agree

• 

  sakshi pawar

  Difference Between Relay and Circuit Breaker | Compare the Difference Between Similar Terms........
  Go to this website, it will clear your ideas😀
• 

  Bijay Krishna Nandi

  I thought question would be better if you have asked difference between a circuit breaker and Isolator as relay and cb has different operations and functionalities. But both are system protective equipments.
• 

  Dabbz

  Circuit breaker is to sense short circuit current and trip in case of short circuit.During selection circuit breaker should be at least 3 times the full load current of the equipment.
  
  Overload relay trips in case of any overload to the equipment and it is to be selected 2 times of the equipment.