what is the function of a circuit breaker ?how does the circuit breaker function during normal operation of an electrical system

2 Answers  

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What are ampers.30kw motor.440volts.

5 Answers   Pam Glatt,

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WHAT IS THE FULL FORM OF ONAN ( TYPE OF COLLING IN TRANSFORMER)

7 Answers  

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suppose MCC (Motor control center)panel work on field the relay on this damage or not work and earth fault occurs in this and no indication in relay panel given below. than MCB trip or not and what effect the panel how find relay will damage or not work.

2 Answers  

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what is iron loss?

4 Answers   RRB,

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Write a note on materials used as a fuse element.

0 Answers   Bhel,

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how we can improve P.F. by using capacitors ?

22 Answers  

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Why battery is always operate on dc supply?

1 Answers   Vikram Ispat Industries,

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Make a list observation on Transformer?

0 Answers   HSL,

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Explain the working of variable frequency transformer?

0 Answers  

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Define liftable weight of a transformer? Does the total weight of transformer include oil weight?

0 Answers  

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When we use air circuit breaker, it has O/L protection ,time delay SC protection, Instataneous SC protection & ground fault protection. They all have some setting range. But what is the suitable/allowable setting for the above protection which will be safe for the equipment? For example-O/L protection setting have a range of (0.4,0.45,0.5,0.55,0.6,0.65,0.7,0.8,0.9,1.0)xIn Time delay SC protection have a range of (1.25,1.5,2,3,4,6,8,10,12)xIn Time delay setting is 0.02,0.1,0.2,0.3,0.4 Instataneous setting is fixed to 20xIn Gound fault setting is given 100A,300A,600A,900A,1200A This setting are for 2500A ACB. So what will be the basic allowable setting for the above protection? is there any formulae to calculate this<

0 Answers   Lupin,

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