Why generally the Rating of Transformers are in additions
of 11 i.e. 11 kVA, 22 kVa, 33 kVA, etc........

Answers were Sorted based on User's Feedback



Why generally the Rating of Transformers are in additions of 11 i.e. 11 kVA, 22 kVa, 33 kVA, etc....

Answer / p. h. godavary

Here the question is not correct. Transformer ratings are never in multiples of 11.

It is the Generator voltages that are in multiples of Form factor 1.1(approx.). The voltages are 3300V, 6600V, 11000V. Consequently the normal distribution / transmitting voltages used are 3.3KV, 6.6KV, 11KV, 33KV, 66KV 110KV, .......

Form factor of an alternating current waveform is the ratio of the RMS (Root Mean Square) value to the Average Value of the waveform]. In the case of a sinusoidal wave i.e. , an analogue wave, the form factor is approximately 1.11

Is This Answer Correct ?    34 Yes 3 No

Why generally the Rating of Transformers are in additions of 11 i.e. 11 kVA, 22 kVa, 33 kVA, etc....

Answer / bharathi

Due to form factor...
The value of form factor is 1.141
So, thats y the rating of transformers r in multiples of
form factor..

Is This Answer Correct ?    18 Yes 5 No

Why generally the Rating of Transformers are in additions of 11 i.e. 11 kVA, 22 kVa, 33 kVA, etc....

Answer / ms.gayathri

The rating of transformer is always not in multiples of 11
i.e., the voltages are only in multiples due to the form
factor. Form factor is nothing but the physical size and
shape of a device. Which is approximately 1.11 derived from
the ratio between RMS value and Average value of the sine
waveform(analog).

Is This Answer Correct ?    11 Yes 2 No

Why generally the Rating of Transformers are in additions of 11 i.e. 11 kVA, 22 kVa, 33 kVA, etc....

Answer / ali

Dears question is why in addition of 11.... that is 22 ..33

Is This Answer Correct ?    8 Yes 14 No

Why generally the Rating of Transformers are in additions of 11 i.e. 11 kVA, 22 kVa, 33 kVA, etc....

Answer / amjad

Due to form factor...
The value of form factor is 1.723
So, thats y the rating of transformers r in multiples of
form factor..

Is This Answer Correct ?    8 Yes 17 No

Why generally the Rating of Transformers are in additions of 11 i.e. 11 kVA, 22 kVa, 33 kVA, etc....

Answer / arun

in above of that rating of transformers only will have very
less harmonics...when compare with other rating...

Is This Answer Correct ?    5 Yes 18 No

Why generally the Rating of Transformers are in additions of 11 i.e. 11 kVA, 22 kVa, 33 kVA, etc....

Answer / denish konsam, manipur

Because the load on the transformer depends upon the power
factor. If it is given in KW then the load will be fixed
that means that transformer can be used for only one load.

Is This Answer Correct ?    6 Yes 25 No

Why generally the Rating of Transformers are in additions of 11 i.e. 11 kVA, 22 kVa, 33 kVA, etc....

Answer / abdul wajid

Basically there are two type of losses in Transformer Iron
losses and core losses Iron losses depend upon voltage and
core losses depends upon current so the total losses
depends upon voltage and current hence transformer ratin is
taken as KVA

Is This Answer Correct ?    11 Yes 50 No

Post New Answer

More Electrical Engineering Interview Questions

why transformer measures in kva

4 Answers  


what will happen if i connect 12 volt battery with 24 volt battery charger.

0 Answers  


our factory is going under construction mean time transformer 1000 kva 2 nos &load break swithch 12 kv & 4 nos 750 kva 2 nos & 380 kva 2 nos generator to be errcted.how to arrange earth pits &how to earth connect & neutral pit how to calculate in earth bit size.

0 Answers  


internally connection of photvoltic module

0 Answers  


why the neutral line is not giving shock to us if we touch it ?

0 Answers   GPREC,






How to calculate motor current for 3 ph & 1 Ph motor from KW rating?

3 Answers  


How do we calculate the resistance per metre of single core aluminium stranded cable 19*3.25mm sheathed in pvc,at 15 deg C temperature?

0 Answers  


why the earth is taken minimum in supplying? wather it the proportional factor to getting work any equipment or a power plant?

0 Answers  


what is meant by loss of field in a DC motor? how a universal motor works?

0 Answers  


I have carried out wiring for lighting in a shed in Industrial area which contains Metal halide lamps & have balanced in 3ph.Now when we put all the lines on in the daytime the current taken at 3phases at MCB comes to be equal i.e.28,29,28Amps respectively but in the night time i.e between 7p.m.to 11p.m. at the same MCb the current is 52,59,62Amp, though I have fit 63A MCB it is tripping in the above period.What may be the reason.? Note: This industry is located in industrial area where majority of steel ingot manufacturing plants are there. Whether this may be due to harmonic? what should I do to overcome above problem.pl suggest urgently.

4 Answers  


11 KV Power cable end earth connection insulation got burned wht is the reson pl give the resons

2 Answers  


11kv = LT 440v , how many amp.supose 440v side 5000 amp curent drown

2 Answers   Motwane,


Categories
  • Civil Engineering Interview Questions Civil Engineering (5085)
  • Mechanical Engineering Interview Questions Mechanical Engineering (4451)
  • Electrical Engineering Interview Questions Electrical Engineering (16632)
  • Electronics Communications Interview Questions Electronics Communications (3918)
  • Chemical Engineering Interview Questions Chemical Engineering (1095)
  • Aeronautical Engineering Interview Questions Aeronautical Engineering (239)
  • Bio Engineering Interview Questions Bio Engineering (96)
  • Metallurgy Interview Questions Metallurgy (361)
  • Industrial Engineering Interview Questions Industrial Engineering (259)
  • Instrumentation Interview Questions Instrumentation (3014)
  • Automobile Engineering Interview Questions Automobile Engineering (332)
  • Mechatronics Engineering Interview Questions Mechatronics Engineering (97)
  • Marine Engineering Interview Questions Marine Engineering (124)
  • Power Plant Engineering Interview Questions Power Plant Engineering (172)
  • Textile Engineering Interview Questions Textile Engineering (575)
  • Production Engineering Interview Questions Production Engineering (25)
  • Satellite Systems Engineering Interview Questions Satellite Systems Engineering (106)
  • Engineering AllOther Interview Questions Engineering AllOther (1379)