Answer / amit sharma

actually a dust particle is having -ve charge and it is
attracted by a +ve charge.
so for the collection of dust particles by the collecting
plates, they should have +ve charge and there is only a way
to get +ve charge.

Answer / ashok jain

becoz we need to attract -ve ions floating .if -ve terminal
is grounded heavy current will blow off all fuses.

UPS battery Back time = no.of Batteries * Ah of the Battery / output KVA * 130 ? what is the 130 means ? can any one help? because all are using this formula how its came 130?

2 Answers  

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IF we have three 30KW motor, these motors are connected in DOL, star-delta and VFD respectively, what will be the fuse rating for the above three?

7 Answers   DOL, GSK, Ojus,

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1.why we are using blocks in withoutgaplightning arrester 2.why we ar using bushing in withoutgap lightning arrestor

0 Answers  

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It is desired to flood light the front of a building 42 meters wide and 16 meters hig.Projectors of 30 degree beam spread and 1000 watt lamps giving 20 lumen/watt are availabl.If the desired level of illumination is 75 lumen/m and show a suitable scheme.Assume the cofficient of utilization, deprecitation factor and waste light factor are 0.4, 13 and 1.2 respectively.

0 Answers  

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What is the difference between EARTH & NEUTRAL?

13 Answers   L&T,

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What is vector group? What is meant by DYN11?Why is it needed?

13 Answers   Areva, Bhel, BRG, Escorts, Fortis,

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what rectifiers is and what are the types of rectifiers?

0 Answers  

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how do we fix the rating of mcb required for a specific capacity of the electric motor

2 Answers  

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What are chief characteristics of state-space method and its techniques ?

0 Answers   Limton,

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Pleasd Tell Me..... In Generating Stations Why The Generation Of ELECTRICITY Is In 3 Phase Form?? OR In Generating Station Why We Generates The ELECTRICITY In The 3 Phase?? Why Not In The 4 Phase, 5 Phase Or 6 Phase Form??

3 Answers  

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In a 132KV Grid Station where voltage level is 132KV, here,  why the rating of Surge arrests installed 120KV ? 

1 Answers  

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In all the generators, the excitation supply is DC. What is the significance of DC excitation? What will happen if AC supply is given as excitation supply?

2 Answers  

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