Answer / dhiraj banka

Class b SPD is for lightning surges & class c SPD is for switching surges.Class B+C protects both from lightning & switching surges.

Answer / vanraj

For surge arrester (lighting arrester) class defines the
capacity of energy can dissipate by SA.

Class in generally not defined by B & C but it defined a
class 2 , Class 3 , Class 4 & class 5 for sub stations.

For 145 kv (110,132 kv ) class 2
For 400 kv ( 400 kv) class 3
For 540 kv (generally not use in india) class 4
For 765 kv Class 5

What is the difference between LT CT & HT CT?Can we use indoor type transformer as an outdoor type or vice versa?

2 Answers   Bhel,

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We have .ht motor which is 60Hz.we run on 50Hz.so that it's speed reduce but we had one prob.that motor winding temp increase up to 135 deg.we want reduce this temp.what to do?we arrange ext.cooling fan but not much effect.we want reduce this temp. Inhouse without affecting much.cost. also don't want reWINDING OF MOTOR?

3 Answers  

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what is the difference between earth, neutral and ground?

1 Answers   Farnek, Shyam Indus Power, Spiro Solutions,

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Why AC & DC capacitor are use in UPS ??????????????????

0 Answers   Sanghi,

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Why usually in all electrical equipment taking more current in Y pahse like pumps,compressor,or any other applications

1 Answers  

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what are factors to be consider to design a HT & LT motor?

0 Answers  

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HOW TO CALCULATE THE DOMESTIC POWER FACTOR?

3 Answers  

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What is the difference between EXE and EXD

1 Answers  

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how to calculate capacitor rating for an induction transformer ex.for 12 mva furnace calculate capacitor rating

2 Answers  

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Is it possible to make 0.75KW motor earthing from MCC panel by using the 1.5 SQMM, 4 core cable, means 3 core for 3 Phases & 1 core for Earth terminal?

4 Answers  

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what will happen if dc motor given ac supply

11 Answers   Mahaveer,

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why we use 3 phase in our country?..why no 4,5 or 2??

2 Answers   Siemens,

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