Answer / md. faruque

A combination of disconnect switches and breakers used to isolate equipment in substations. It refers to electrical equipment that regulates the flow of electricity within an electrical system. It is used by utility providers and private facilities alike for two reasons: to prevent overloads and short circuits, and to de-energize circuits for testing and maintenance. The most familiar types of switchgear are circuit breakers , fuses & lighting arrestors, which interrupt the flow of electricity to a circuit when its current becomes too high and directly pass the surge voltage to earth.
Main considerations in apparatus protection – transformer, generator and motor protection – protection of busbars. Transmission line protection – zones of protection.CTs and PTs and their applications in protection schemes.
Types of circuit breakers – air blast, air break, oil, SF6 and vacuum circuit breakers. Types of lighting arrestors are- horn gap, expulsion type, gapless metal oxide type etc. It is also classified on the basis of class.

Answer / k.prakashchandra

Switch gears include c.b.and isolators

Answer / younas

what is the important think in switchgear room

if there are six generators (3 gas CATT, one Jenbacher o1 MW each, and two nos Diesel 01 no 01 mw other 0.65mw EDGs ( say), 3 CAtt gas set have identical pole pitch,01mw EDG and Jenbacher gas Set have different pole pitch, how their power connection can be done to connect a common bus bar during installation. in short, how different pole pitched generators power connection can be done to connect a common busbar system through generators incomer ACBs.

0 Answers  

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WHAT IS MEANT BY OVER EXCITATION IN GENERATOR TRANSFORMERS? DESCRIBE IT.

0 Answers  

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7/20,3/20 electrical wire is specified as stated.Why?

1 Answers   TCS,

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In a Dyn11 transformer, how are the 3 windings of the delta connected? Assume that R1-R2, Y1-Y2, B1-B2 are the 3 windings on the HV side.

3 Answers  

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which type of oil is used as a transformer oil?

3 Answers   JSW,

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How to select a transformer group to connect a 0,433 KV generation with 33 KV grid in bi directional flow of current

0 Answers  

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how to calculate overall efficiency of diesel generator set? give us a formula with an example.

2 Answers  

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What is transister , thermister , thyrister? what is its function? where this using?

1 Answers  

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why the transformer has no starter

2 Answers   NTPC,

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how much percentage(%) of load can feed in power transformer?

1 Answers   Siemens,

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what is ramping rate of generator

0 Answers   Core,

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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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