Answer / ktd

CT class is basically indicating the purpose and accuracy
of the CT. In brief
class 1.0 indicated +/-1% variation in the Current measured
by the CT. ex. a CT with ratio 100/1 with Cl. 1, measuring
100A in the conductor can possibly show 1.01A or .99 A
deviating 1% max from the actual reading.

class 5P20 indicates a protection class CT which can
withstand 20 times the rated current(occuring due to faults)

Answer / karthik raman.b

it has 2 class metering and protection

Answer / rajesh dhankar

CT class is the class of accuracy of instrument standardised
by indian standard (ISO).
For example if a CT out put is of 5 ampere if it gives out
put between 4.5 to 5.5 ampere than it is with in limit but
if it increase than it is out of limit and needs to be
replaced making electrical department loss of lakh per year.

How damper winding in synchronous motor suppress Hunting?

2 Answers   Bhel,

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What will happen if supply to three phase motor is given wiyhout inerting rotor in it?How much current it will draw?

5 Answers  

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how much earthings are mendatory at a 25kva sub station?

3 Answers   Bhel,

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How to find Cable size? Caterpillar generator produce (Two generators) 127*2=254 amp at 11 kv . What would be the cable size (XLPE) to supply 256 amp at 11 kv? Air or surrounding Temperature is 32 degree C. Cable will go under ground at 2.5 feet depth. Group Rating Factors is 3 cables. Clearance between cables is 7 cm. Soil Temperature (Ambient) 28o C Soil Thermal Resistivity is 1.2 K.m/W I would like to use 3 separate single core instead of using 3 core cable. Some says I should use three separate single core 120RM cables. Some says 70RM .some says 95. I m totally confused. Is there ant specific rule to determine cable size? What would be the LT cable size to flow 500 Amp current? Ifte My e mail address is ifte13@yahoo.com Anyone please send me the answer to my e mail address, i will be very glad.

1 Answers  

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what is pressure relief valve?where it is used????

4 Answers   Mecon,

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what can be the causes of capacitor start motor having a higher current that its actual

0 Answers  

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Frequency in the control system represents? Continuous system in time domain ? In frequency domain?

1 Answers   CCP,

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we have one pumping station and 4.6 MW 7 no.s synchronous motors.so there is no required HT capacitor to improve power factor.But we have two no.s of 25 Mva power transformer connect to distribute the power for motors connect with 220 kv line.So i have required the HT capacitor to improve power factor at HT side i mean power transformer bus side.So please suggest how much HT capacitor banks required for same.

1 Answers  

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what will happen if dc supply is given to ac motor?

9 Answers   CTS,

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why 3 phase is preferred than 1 phase?

4 Answers   Infosys,

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i have 60Hz motor, can i run it at 50Hz power supply ???

2 Answers  

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we done magnetic balance test for 33KV /440V transformer in our company , but the ratio out is confusing us Voltage applied in RY = 440 , at RB = 320 and YB = 60 RY 440 = ( RB + YB ) 380 only Please let me know what type of problem is it.

2 Answers  

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