Question { 8106 }

An electric bulb giving light but at the time of lighting
which one it takes? voltage or current

Answer

At the time of lighting, current will flow through the tungsten by means of potential difference(Voltage). Due to this, the heat will produced and come out.

Question { 6303 }

why we use to always generate power below 16kv.why not at
higher voltage?

Answer

Normally, in India, the generating voltages are 6.6 KV,11 KV. Very rarely 22 KV, 33 KV are generating. If generating voltage increases, the cost of alternators, protecting devices abd other equipments are increased.

We can stepped up / down the voltage as we required by using transformers. So minimum generating voltage is efficient and economical.


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Question { 5367 }

why transmission line towers are longer than communication
line towers?

Answer

The transmission lines are very high voltage(>11 KV) and also due to harmonic effect, the signals from communication line are highly interrupted. Hence the transmission lines towers are built up very longer.


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Question { 12062 }

why transformer capacity is called KVA and motor capacity
is called HP/KW?
Why transformer capacity cant call HP/KVA?

Answer

Transformer is a static device(no moving parts). The voltage transmission is through mutual inductance(M=L.dI/dt). So losses in transformers are meaning less.So the Power in transformers are mentioned in VA or KVA or MVA.

But in motors are having moving parts. so the inductive coil(Rotor or field)have lagging power factor. The phase difference between voltage and current is called power factor.

The losses in motors are very high compared with transformers. So in motor, the power is noted as KW.

(Note: 1HP=746 Watt or 0.746 KW)


ersaravananp@gmail.com

Question { RasGas, 7487 }

WHAT IS VFD,FUNCTION, PURPOSE,

Answer

In Electrical:- VFD(Variable Frequency Drive). This is used to monitoring and controlling the speed of the driven based on the variation of frequency.

In Mechanical:- This is used to control the flow of air within the duct in terms of CFM(Cubic foot Metre).

Question { 18753 }

what is the difference between electrical wire and
electrical conductor?

Answer

Electrical wiring is also the conductors. But the wire is the single or multi strand with round shape in cross section.

Other materials like Cu / Al flat, Bus bar, Bus duct are generally called as the conductors.



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Question { 11670 }

Wat is the best to use in a generator a 6.5kva or a 7 kw

Answer

Generator ratings are always noted in KVA, not in KW. The ratings are designed based on the load dependency.

From your question,6.5 KVA is better than 7 KW(8.75KVA Aprox.)


ersaravananp@gmail.com

Question { 11670 }

Wat is the best to use in a generator a 6.5kva or a 7 kw

Answer

Hi Jaswinder, the DGs are designed based on the load dependency only. If you are bring the DG in higher rating for low load then no meaning of efficiency.

Hence, 6.5 KVA or 7 KW(8.75 KVA) are doesn't matter. It is fully depends on the magnitude of load.


ersaravananp@gmail.com

Question { Synergy, 6293 }

what is the diffrence between mcb &elcb?

Answer

MCB - Miniature circuit breaker:- Which helps to avoid over current or fault current enter into the circuit.It protect the circuits by tripping operation.This is available up to 63A.

ELCB - Earth leakage circuit breaker:- Which helps to avoid the running current enter into the earth by means of tripping operation.This is available up to 63A.



ersaravananp@gmail.com

Question { TCS, 6755 }

What is frequency?

Answer

Frequency is the no. of cycle passing by alternating
current in a Second.

Frequency is the inverstly proportional to the time.(F=1/t).

Question { 9912 }

Describe the method of Plate Earthing.

Answer

Plate earthing provids using copper plate (450mm x 450mm x
6mm). The area of the copper plate is high causing high
earthing value (Low resistance).

Instaling Method: The copper plate at the depth of 2 Mtr or
3 Mtr. The centre support provides using 40mm GI pipes,
funnel in top.The two numbers of 25mm x 3 mm copper flat
stamped from top of the GI pipe to copper plate to improve
the earth value. The salt, charcole to improve the
conductivity.

The materials using for plate earthing are as below:

1) Meshed Funnel
2) 40 x 300 x 6 mm copper earth pad
3) 25 x 3 Cu strip
4) Copper Rivit
5) 450 x 450 x 3 mm Cu plate
6) 8x25 mm bolt and nut with washer
7) 6x75 mm bolt and nut with washer
8) 40 mm GI pipe - 2.8 mtrs
9) 25mm dia x 200 mm length GI pipe with double end threaded
10) 40mm to 25 mm GI reducer
11) 1" Check nut(6mm thick)
12) Charcoal
13) Salt
14) 450 x 450 mm heavy duty SFRC chamber cover with frame



ersaravananp@gmail.com
Saravanan.P

Question { 13718 }

List the materials required for Pipe Earthing.

Answer

Meshed Funnel earthing:

1) 50 x 300 x 6 mm GI earth pad
2) 50 x 6 GI Flat with sleeves
3) 25mm Check nut(6mm thick)
4) 25mm dia x 200 mm length GI pipe with double end threaded
5) 40mm to 25 mm GI reducer
6) 40 mm GI pipe - 2.8 mrs
7) Charcoal
8) Salt
9) 6x75 mm bolt and nut with washer
10) 8x25 mm bolt and nut with washer
11) 450 x 450 mm heavy duty SFRC chamber cover with frame
12) 25 x 6 GI Flat



ersaravananp@gmail.com