Answer / k.prakashchandra

Back up time is decided by batteries and the load.The
formula is simple. B/U time in hrs = stored energy in
batteries (AH x V(both of each battery) X Number of
batteries)/Load in Watt

what is the funda of earthing? Explain breifly about earthing?

5 Answers   IOCL,

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Can I use cable armour as a earth conductor? if not how many GI/CU wires I need to run along with cable?

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How to calculate per unit impedance of transformer?

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What is ZCT? it operating principle and how is work with RCCB (residual current circuit breaker)?

4 Answers  

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which MPU register provides the address from which the next instruction byte is to be fetch?

1 Answers  

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Hi, I'm running plastic reprocessing company where all motors are running only in delta. Due to that when I use start my 30 hp motor my transformer gets fuse. Where it happens two times a day. I gt a suggestion from a person about Automatic Power Factor Controller APFC. Is it useful for my problem??? Or is der any other way for solving this problem?? Upgrading the transformer is difficult. Pls give Me ur suggestion. Waiting for ur reply.

2 Answers   Shree Lingaa Polymer,

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Q) Write VBscript code along with QTPscript code in QTP tool for below scenario 1. Launch yahoo site(i know) 2. Do loogin(i know) 3.Click inbox link(i know) 4.Go to every page of mail box and count no.of read mails and no.of unread mails(i know) 5.Store page numbers, read mail count and unread mail count in a new excel file sheet 6.Create 10 types of graphs on that data 7.Do logout and close site(i know) 8.Save new excel files with graph

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What is SFU why it is used

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Why do we use copper cable for HT Supply and why not Aluminium?

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when we are going to higher voltage level in substations why we are using Sf6 circuit breakers instead of Vacuum circuit breakers.

3 Answers  

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how many transformer

8 Answers   Dalmia Group, TATA,

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Energy metering: On the property I am renting, the supply voltage is 2 x 110 volts. These 2 x phases enter a energy meter which then exit the meter to over head lines to my house. Question 1. The meter is single phase 240 volts but is being used as 2 x phase(2 x 110volt), is this acceptable? if not, please give me the reasons. The meter details are as follows: 60Hz 15amp Imax 100 amp Kd 3,6 Wh/R 1 fase 3 hilos Model FX 231. I think it was manufactured in Brasil From this meter, the cables run along over head aluminum conductors,I estimate the cross sectional area to be 25mm diameter, but the neutral is only about 10mm square diameter, which cover a distance of 170 meters and then terminate with an underground cable of 65 meter length, total length = 235 meters. There must be a huge voltage drop over this length. This line is protected with 2 x 200 amp aluminum fuses after the meter, there is no main switch in the distribution board. These 2 phases connect directly onto 2 busbars. Surely the neutral should be the same size as the conductors if not more? Question2. What are your thoughts about this installation, should there be better protection, is the neutral too small? During the night, the lights dim then brighten all the time, this cannot be good for my electrical appliances. In my home, I only have a small electric geyser and fridge, my stove works off gas. But when i use other appliances like the washing machine or microwave oven, the light dim. The internal wiring of this house is done with solid hard drawn copper wires and of course, they have to be under rated. I am a retired electrician by trade, but not on the metering and over head mains side, my experience is on the factory maintenance side of things. Your expertise on these matters will be greatly appreciated. Please inform me how to rectify or make any improvements Kind regards, my power bill is very expensive, so I need to know how to bring it lower. Kind regards, Brian

1 Answers  

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