Answer / Sumit Batham

The derating factor of a cable is used to reduce its current-carrying capacity and lifespan to account for temperature rise, voltage drop, and other factors. This helps ensure safe and reliable operation over extended periods. The importance of the de rating factor lies in preventing cable failures due to overloading or thermal stress, minimizing downtime, and maintaining safety standards.

explain me how a power factor is improved by adding a capacitor?what capacitor do to improve it?in simple words and in detail?thx

7 Answers  

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There is one 40MVA oil cooled transformer (yet to commission), filled with 95% oil and we are trying to fill 5% Nytrogen in that transformer so that there should not be any foreign component inside. But even though there is no leakage, nytrogen is not withstanding inside transformer, within a day or two pressure guage is showing 0. Why is it soooo? Pls reply.

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what is the safe meggar values for motor, transformer HT, LT and Cables? IF we want to replace I/C bay at our 220 kv substation which is of 140 mw load capacity bay to be replaced by 400 mw capacity bay.other than CT(1200/1) what are the other equipment i have to replace. why we generally use 3.5 core cable or in other word 1/2 core for neutral and also confirm me that in balance conditiob(3 phase)current in neutral will zero

1 Answers   Jindal,

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What is ferro-resonance in electrical system? Why it occurs and what are measures to prevent it?

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for 1000kva transformer how kvar rating is need for this PFI plant. and how does it will calculate? and Apmpere rating of main cable connection?

6 Answers   Engineers India, GCC, KP, QPSL, Siemens,

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How is a capacitor bank is designed ?

2 Answers   Asian Paints,

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How to calculate the load loss and no load losses of the power Transformer? i am having the following details : full load ct : in AMP HV :1676 ; LV:31.5 1800 KVA ;33KV/620 V for wind mill applications

2 Answers   ReasonSoft,

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which oil used in transformer?

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I have been short listed for sydicate clerkcal post .i have interview on 15th sept..i want to ask if i don't know kannada to read and write they won't allow me to attend the interview?Do send u r reply.......

1 Answers   Syndicate Bank,

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why can not run two different phase circuit in to the same conduite

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Whether we used insulated line for 33KV supply. what we called it.

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how to identify conection leads of an unknown electric motor

1 Answers  

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