Answer / h s sandhu

Since there is oil in the transformer and with the load increasing the temp of oil increases because of more current flowing in HT/Lt windings .We measure the temp of oil with the max limit st as per Is of the transformer.( 90deg above ambient )

Answer / jithendra

 Transformer oil is a medium for Transformer winding to decrease the winding temperature when load increases simultaneously winding temperature increases, so oil is used & also it is insulated oil.

Answer / rutulsoni

in trasformer there is increase in temprature with increase load.we measured temp of transformer to measured insulation resistance of device.it shoud not excedd above 85 C in oil tank and shoud not exceed above 95 C between winding...is this right? pls give me feed back

we have a 2000kva step down transformer at our site. The HT side is charged from 22000V. So the primary current will be 52.48A. So why the HT breaker(SF6 ABB) is rated of 1250Amps ?

2 Answers  

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why and how fault current flows through ground?

1 Answers  

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What is meant by system?

0 Answers  

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what is difference between RCB,RCCB &RCBO?

3 Answers   ABB,

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following are the questions asked in interviews: 1) Considering the short circuit fault, which switchgear is preferable, SFU OR MCCB? Which operates faster? whicg one is popular in Indian Market and why? 2)Define SCPD. What is type2 coodination? 3)Why the contactor rating is higher for the fuseless selection than for fuse selection? whether the ratinf of SFU or MCCB remains the same in both the cases? 4)If the HP rating is known then can you calculate the ratings of L.V Switchgear(SFU/MCCB, contactor, OLR) without using the selection chart?

0 Answers  

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Explain the working of variable frequency transformer?

0 Answers  

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what is settable hystersis protection? If any body knows plz kindly post the answer..

0 Answers  

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what is rated speed?

4 Answers   Actavis,

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What is the difference between PLC & DCS?

1 Answers   Power Plant,

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1. If we apply dc supply to the primary winding of transformer it will be burnt out. similarly dc supply is given to field winding of syn. motor and armature winding of dc motor, they are safe. (Remember both windings inductive nature) what is the reason behind that?

2 Answers  

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Brief use of isolation transformer & how it works.

1 Answers  

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Which one hurts more AC or DC Current ?

10 Answers  

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