Why all voltage level are multiples of 11, like 220V, 440V, 1100V instead of 2

Categories >> Engineering >> Electrical Engineering
Suggest New Category

Why all voltage level are multiples of 11, like 220V, 440V,
1100V instead of 200V, 400V, 1000V?

Question Posted / md shahnawaz

9 Answers
21271 Views
Indian School of Mines, I also Faced
E-Mail Answers

Answers were Sorted based on User's Feedback

Why all voltage level are multiples of 11, like 220V, 440V, 1100V instead of 200V, 400V, 1000V?..

Answer / bikash

since all the voltage generation are in average and we use
rms quantities for computation. so we need to convert the
average to rms simply by multiplying the form factor 1.11.
thats how the voltage levels are in the multiple of 11.

Is This Answer Correct ?

56 Yes

8 No

Why all voltage level are multiples of 11, like 220V, 440V, 1100V instead of 200V, 400V, 1000V?..

Answer / thunder bird

AC voltages are sinusoidal in propagation. the electrical machines are designed for root mean square(RMS) values of voltage which is nothing but equivalent D.C voltage.whereas insulation, transmission etc are calculated for average(AVG) values which is 1.1 times RMS value.1.1 is form factor for sinusoidal waves. (form factor = RMS value/ AVG value). so a generator may be producing 400 kV RMS but in common mans' term it will be 440kV.

Is This Answer Correct ?

4 Yes

3 No

Why all voltage level are multiples of 11, like 220V, 440V, 1100V instead of 200V, 400V, 1000V?..

Answer / girish

AC sine wave form factor will be of RMS value / Average value
of a sine wave, that will be 1.11, so all voltage levels are
multiples of 11

Is This Answer Correct ?

4 Yes

4 No

Why all voltage level are multiples of 11, like 220V, 440V, 1100V instead of 200V, 400V, 1000V?..

Answer / sakthi

its a historical reason. initial days design people assumed that line losses will be around 10%. so they have designed to 110% to get 100%. but nowadays it has been changed. now we are using 400V instead of before 440V. 230V instead of 220V before. There is nothing to do with form factor. its not involving any of the design calculations.

Is This Answer Correct ?

3 Yes

3 No

Why all voltage level are multiples of 11, like 220V, 440V, 1100V instead of 200V, 400V, 1000V?..

Answer / cheech

just for shits & giggles

Is This Answer Correct ?

2 Yes

2 No

Why all voltage level are multiples of 11, like 220V, 440V, 1100V instead of 200V, 400V, 1000V?..

Answer / mohamed

We are designed the alternators windings should be wound '11o' clock position.

Is This Answer Correct ?

0 Yes

3 No

Why all voltage level are multiples of 11, like 220V, 440V, 1100V instead of 200V, 400V, 1000V?..

Answer / sreeknp

when converting average value to r m s multiplication factor
is 1.11 hence voltages

Is This Answer Correct ?

4 Yes

8 No

Why all voltage level are multiples of 11, like 220V, 440V, 1100V instead of 200V, 400V, 1000V?..

Answer / aks

we don't now. Mr.MD.Shahnawaz pls tell the correct answer.

Is This Answer Correct ?

2 Yes

13 No

Why all voltage level are multiples of 11, like 220V, 440V, 1100V instead of 200V, 400V, 1000V?..

Answer / sundeep

Because anywhere the generator rating is 11kv...so the
voltages are stepped up or stepped down in the multiples of
11...

Is This Answer Correct ?

3 Yes

16 No

Post New Answer

More Electrical Engineering Interview Questions

1. Synchronization is not required A. Thermal B.Hydel C.Wind D.Nuclear

2 Answers APGenco, Birla Power,

why are the transmission lines operated at 220 kv nly... nt les dan dat...

3 Answers

If we increase frequency in transmission line in lieu of voltage what will happen?

1 Answers

In a generator (Synchronous) does the rotor speed (frequency) corresponds to the speed of the water (in hydro). does the torque on the turbine relate to the flow of water?

2 Answers

There is 15 KVA UPS using for single phase load.And 30 batteries of 12 V, 100 Ah are connected in series. Load is taking 15 A current.What will be the back up power for this UPS on same load?

1 Answers BS, Dynamic Software,

How to control motor gearbox speed and friquency? If length of cable and dia given, how to measure the voltage drop?

0 Answers

what is field flash

4 Answers Bhel,

Difference between a pilot wire and a normal conductor?

0 Answers United Arab Aluminum Company,

When One Phase PT Missing (voltage drop ) this time current is zero of This phase(PT Missing Phase) and current is Not Zero of other Phase but PF is always Low That Why

0 Answers HCL,

What is the different between buchholz relay and pressure relief device?

2 Answers

what is the function of a circuit breaker ?how does the circuit breaker function during normal operation of an electrical system

2 Answers

How to measure corona loss in a transmission line?(Plz ans only if u know the exact answer)

3 Answers

For more Electrical Engineering Interview Questions Click Here