Recent questions tagged breaker

Description : Explain about Circuit Breaker

Last Answer : Ans: CIRCUIT BREAKERS: In the case of outdoor type installation, the circuit breakers have fixed location and the station layout is such that adequate section clearances are always available from ... carried out as above, every circuit breaker will be completely overhauled after five year interval.

Description : How to Reset a Circuit Breaker

Last Answer : How to Reset a Circuit Breaker All is well with the lights and your electrical appliances one minute, then everything falls into pitch-black darkness the next moment. When a room in your house ... electrical fires. With these tips, a power surge does not have to be a permanent inconvenience.

Description : How to Install a Circuit Breaker

Last Answer : How to Install a Circuit Breaker A circuit breaker is an essential component of a home's electric system. When power surges occur, it trips then shuts off the electricity, preventing ... -functional electrical system. Just make sure you take proper safety precautions when installing this device.

Description : Explain working of static AC circuit breaker. 

Last Answer : Static AC Circuit breaker: The circuit configuration of static AC circuit breaker using SCR is shown in the figure. When switch S' is closed, the SCRs T1 and T2 are fired in positive ... non-availability of gate current. Thus the maximum time delay for breaking the circuit is one half-cycle.

Description : Explain working of AC circuit breaker using SCR with circuit diagram.

Last Answer : AC Circuit Breaker:  The circuit configuration of static AC circuit breaker using SCR is shown in the figure. When switch S' is closed, the SCRs T1 and T2 are fired in positive ... to non-availability of gate current. Thus the maximum time delay for breaking the circuit is one half-cycle.

Description : State function of starter and ELCB. (Earth Leakage Circuit Breaker)

Last Answer : i) Function of Starter:- 1. To prevent the high starting current OR to minimize the starting current. 2. To give supply failure protection 3. To give over load and short circuit protection ... an installation and cut off the circuit from power supply and avoid electrical shock to the person.

Description : The arc temperature in Oil Circuit Breaker may reach up to_______.  (A) 5,000° K (B) 8,000° K (C) 10,000° K (D) None of the above

Last Answer : The arc temperature in Oil Circuit Breaker may reach up to 5,000° K 

Description : The number of cycles in which a high speed circuit breaker can complete its operation is  (A) 3 to 8 (B) 10 to 18 (C) 20 to 30 (D) 40 to 50

Last Answer : The number of cycles in which a high speed circuit breaker can complete its operation is 3 to 8

Description : A circuit breaker is designed to protect an electrical circuit from damage caused by :  (A) Over load (B) Short circuit (C) Over current (D) All of the above

Last Answer : A circuit breaker is designed to protect an electrical circuit from damage caused by :  (A) Over load (B) Short circuit (C) Over current (D) All of the above

Description : The Minimum Oil Circuit Breaker (MOCB) is named because of :  (A) Reduced requirement of oil (B) Reduced requirement of air (C) All of the above (D) None of the above

Last Answer : The Minimum Oil Circuit Breaker (MOCB) is named because of : Reduced requirement of oil 

Description : Breaking capacity of a circuit breaker is usually expressed in terms of  (1) Ampere (2) Volts (3) MW (4) MVA

Last Answer : Breaking capacity of a circuit breaker is usually expressed in terms of MVA

Description : For selecting a circuit breaker, ______ should be determined.  (A) initial current that flows on occurrence of a short circuit only (B) transient current that flows at the time of circuit interruption only (C) resonant frequency only (D) (A) and (B) 

Last Answer : For selecting a circuit breaker, ______ should be determined. (A) initial current that flows on occurrence of a short circuit only (B) transient current that flows at the time of circuit interruption only (C) resonant frequency only (D) (A) and (B) 

Description : The arc voltage in a circuit breaker is :

Last Answer : The arc voltage in a circuit breaker is : in phase with the arc current

Description : Which of the following is used in a circuit breaker as the medium in which the arc forms? A) Insulating gas B) Insulating oil C) Vacuum D) All the above

Last Answer : Which of the following is used in a circuit breaker as the medium in which the arc forms? A) Insulating gas B) Insulating oil C) Vacuum D) All the above

Description : ln a minimum oil circuit breaker the oil is used

Last Answer : ln a minimum oil circuit breaker the oil is used to act as circuit breaking medium only

Last Answer : Arc in a circuit breaker is interrupted at zero current.

Last Answer : The arc voltage produced in A.C. circuit breaker is always in phase with the arc current.

Last Answer : In a circuit breaker the basic problem is to transmit large power.

Last Answer : Ionization in circuit breaker is facilitated by high temperature, increase of mean free path, increasing field strength.

Last Answer : The voltage appearing across the contacts after opening of the circuit breaker is called recovery voltage.

Last Answer : Air blast circuit breaker is used for repeated duty.

Last Answer : Magnetic circuit breaker has instantaneous trip action.

Last Answer : Thermal circuit breaker has delayed trip action.

Last Answer : The arcing contacts in a circuit breaker are made of copper tungsten alloy.

Description : what is SF6 circuit breaker?

Last Answer : SF6 is Sulpher hexa Fluoride gas. If this gas is used as arc quenching medium in a Circuit breaker means SF6 CB.

To see more, click for the full list of questions or popular tags.