The arc voltage produced in A.C. circuit breaker is always?

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

1 answer

431 views

The voltage appearing across the contacts after opening of the circuit breaker is called______voltage.

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

1 answer

285 views

Arc in a circuit behaves as?

Description : Arc in a circuit behaves as?

Last Answer : Arc in a circuit behaves as a resistance decreasing with voltage rise across the arc.

1 answer

659 views

The number of cycles in which a high speed circuit breaker can complete its operation is

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

1 answer

106 views

A circuit breaker is designed to protect an electrical circuit from damage caused by :

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

1 answer

167 views

The Minimum Oil Circuit Breaker (MOCB) is named because of :

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

1 answer

80 views

For selecting a circuit breaker, ______ should be determined.

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)

1 answer

85 views

ln a minimum oil circuit breaker the oil is used

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

1 answer

122 views

In a circuit breaker the basic problem is to?

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

1 answer

308 views

Ionization in circuit breaker is facilitated by?

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

1 answer

79 views

Air blast circuit breaker is used for?

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

1 answer

221 views

Magnetic circuit breaker has ______ trip action.

Last Answer : Magnetic circuit breaker has instantaneous trip action.

1 answer

156 views

Thermal circuit breaker has?

Last Answer : Thermal circuit breaker has delayed trip action.

1 answer

119 views

The arcing contacts in a circuit breaker are made of?

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

1 answer

99 views

what is SF6 circuit breaker?

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.

2 answers

29 views

Explain about Circuit 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.

1 answer

11 views

How to Reset a Circuit Breaker

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.

1 answer

15 views

How to Install a Circuit Breaker

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.

1 answer

216 views

Explain working of static AC circuit breaker.

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.

1 answer

949 views

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

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.

1 answer

469 views

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

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.

1 answer

279 views

Breaking capacity of a circuit breaker is usually expressed in terms of

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

1 answer

260 views

Source transformation Replace the circuit with voltage source in series with a single resistor

Description : Source transformation Replace the circuit with voltage source in series with a single resistor

Last Answer : Source transformation Replace the circuit with voltage source in series with a single resistor

1 answer

352 views

An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic

Description : An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic field having a component along the axis will be (1) unaffected (2) decreased (3) increased (4) either decreased or increased depending on the direction of the DC field

Last Answer : An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic field having a component along the axis will be either decreased or increased depending on the direction of the DC field

1 answer

2.1k views

A DC voltage source is connected across a series RLC circuit. Under steady-state conditions, the applied DC

Description : A DC voltage source is connected across a series RLC circuit. Under steady-state conditions, the applied DC voltage drops entirely across the

Last Answer : A DC voltage source is connected across a series RLC circuit. Under steady-state conditions, the applied DC voltage drops entirely across the C only

1 answer

164 views

What is the RMS voltage in a series RL circuit, if the voltage across R and L is 256 V and 192 V respectively?

Description : What is the RMS voltage in a series RL circuit, if the voltage across R and L is 256 V and 192 V respectively? A) 320 V B) 448 V C) 64 V D) None of these

Last Answer : What is the RMS voltage in a series RL circuit, if the voltage across R and L is 256 V and 192 V respectively? A) 320 V B) 448 V C) 64 V D) None of these

1 answer

109 views

A circuit that binds the upper or lower extreme of a waveform to a fixed DC voltage level is called ______

Description : A circuit that binds the upper or lower extreme of a waveform to a fixed DC voltage level is called ______ A) DC voltage restorer B) Clamping circuit C) Both A and B D) None of these

Last Answer : A circuit that binds the upper or lower extreme of a waveform to a fixed DC voltage level is called ______ A) DC voltage restorer B) Clamping circuit C) Both A and B D) None of these

1 answer

306 views

A d.c. source has an open circuit voltage of 30 V and an internal resistance of 1.5 Ohm. A resistive load is ...

Description : A d.c. source has an open circuit voltage of 30 V and an internal resistance of 1.5 Ohm. A resistive load is connected to the source. Maximum power dissipated in the load is (A) 300 W (B) 150 W (C) 45 W (D) 20 W

Last Answer : A d.c. source has an open circuit voltage of 30 V and an internal resistance of 1.5 Ohm. A resistive load is connected to the source. Maximum power dissipated in the load is 150 W

1 answer

0 views

What should I get for my first welder, arc or stick?

Description : What should I get for my first welder, arc or stick?

Last Answer : ‘pends, I think you should get the arc.

1 answer

266 views

Compare the AC and DC Arc lamps.

Description : Compare the AC and DC Arc lamps.

Last Answer : AC Arc Lamp DC Arc Lamp Cross section area of electrode is same Cross section area of electrode is positive rod is twice that of negative rod Series inductor is used for stability ... supply is used for DC arc lamp Luminous efficiency is less Luminous efficiency is high

1 answer

119 views

Compare between Resistance welding and Arc welding on any six points.

Description : Compare between Resistance welding and Arc welding on any six points.

Last Answer : Sr.No Parameters Resistance Welding Arc Welding 1 Type of welding Plastic/Pressure/Non-fusion welding Fusion/Non pressure welding 2 Principle of heat developed Heat ... It is suitable for mass production It is suitable for heavy job, maintenance and repair work

1 answer

61 views

Write the purpose of coal and ash handling unit. Also write different activities that arc carried out in this unit.

Description : Write the purpose of coal and ash handling unit. Also write different activities that arc carried out in this unit.

Last Answer : Purpose of coal and ash handling unit :- To transport coal from coal storage to power plant. A large quantity of ash about 10 to 30 % produced in furnace, the removal of ash from boiler furnace ... disposed off. Various methods of disposal of ash: Mechanical system. Pneumatic system.

1 answer

80 views

Arc resistance

Description : Arc resistance (1) increases with increase in arc current (2) decrease with increase in arc current (3) is independent of arc current (4) is independent of arc length

Last Answer : Arc resistance decrease with increase in arc current

1 answer

192 views

For arc welding current range is usually

Description : For arc welding current range is usually (1) 10 to 15 A (2) 30 to 40 A (3) 50 to 100 A (4) 100 to 350 A

Last Answer : For arc welding current range is usually 100 to 350 A

1 answer

169 views

Identify the correct combination of respective Electric arc welding and Electric resistance welding methods :

Description : Identify the correct combination of respective Electric arc welding and Electric resistance welding methods : (A) Butt welding and Seam welding (B) Hydrogen shielding and Projection welding (C) Seam welding and Coated electrode welding (D) Coated electrode welding and Hydrogen shielding

Last Answer : Identify the correct combination of respective Electric arc welding and Electric resistance welding methods : (A) Butt welding and Seam welding (B) Hydrogen shielding and Projection welding ... Seam welding and Coated electrode welding (D) Coated electrode welding and Hydrogen shielding

1 answer

93 views

The supply for arc welding is :

Description : The supply for arc welding is :

Last Answer : The supply for arc welding is : Low voltage, high current ac or dc voltage

1 answer

19 views

Refer to the circuit below. The total absorbed (consumed) power is:

Description : Refer to the circuit below. The total absorbed (consumed) power is:

0 answers

32 views

A battery of e.m.f. 12V supplies a current of 5A for 2 minutes. How much energy is supplied in this time?

Description : A battery of e.m.f. 12V supplies a current of 5A for 2 minutes. How much energy is supplied in this time?

0 answers

37 views

The arc voltage produced in A.C. circuit breaker is always (a) in phase with the arc current (b) lagging the arc current by 90" (c) leading the arc current by 90° (d) none of the above

Description : The arc voltage produced in A.C. circuit breaker is always (a) in phase with the arc current (b) lagging the arc current by 90" (c) leading the arc current by 90° (d) none of the above

Last Answer : (a) in phase with the arc current

1 answer

348 views

Which of the following medium is employed for extinction of arc in air circuit breaker ?

Description : Which of the following medium is employed for extinction of arc in air circuit breaker ?(a) Water (b) Oil(c) Air (d) SF6

Last Answer : Which of the following medium is employed for extinction of arc in air circuit breaker ?(a) Water (b) Oil(c) Air (d) SF6

1 answer

3.0k views

If the % reactance upto the fault point is 20%, then the short circuit current will be

Description : If the % reactance upto the fault point is 20%, then the short circuit current will be

Last Answer : If the % reactance upto the fault point is 20%, then the short circuit current will be 5 times the full load current

1 answer

306 views

Which of the following circuit breakers has high reliability & minimum maintenance?

Description : Which of the following circuit breakers has high reliability & minimum maintenance? (A) Bulk oil type CB (B) Air blast CB (C) Vacuum CB (D) Sulphur hexafluoride CB

Last Answer : Which of the following circuit breakers has high reliability & minimum maintenance? (A) Bulk oil type CB (B) Air blast CB (C) Vacuum CB (D) Sulphur hexafluoride CB

1 answer

112 views

The following is/are the characteristics of SF6 circuit breakers:

Description : The following is/are the characteristics of SF6 circuit breakers: (A) It does not need an auxiliary breaking chamber (B) Short break time of 2 to 2.5 cycles (C) All of the above (D) None of the above

Last Answer : The following is/are the characteristics of SF6 circuit breakers: (A) It does not need an auxiliary breaking chamber (B) Short break time of 2 to 2.5 cycles (C) All of the above (D) None of the above

1 answer

165 views

A fuse in a motor circuit provides protection against?

Last Answer : A fuse in a motor circuit provides protection against short-circuit and overload.

1 answer

210 views