Why we are use 11KV / 22KV / 33KV / 66KV / 110KV / 230KV / 440KV this type of ratio. Why can’t we use other voltage ratio like 54KV / 99KV etc.

Why we are use 11KV / 22KV / 33KV / 66KV / 110KV / 230KV / 440KV this type of ratio. Why can’t we use other voltage ratio like 54KV / 99KV etc.
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1 Answer

Answer :

1. When an alternator generates voltage, its rms value is given by 4.4*f*$*t, where $ is value of total flux per pole. So we can see all the voltages are made inevitably multiple of this value (1.1, which is the form factor of ac wave). Also it provides us the best economic construction of step up and step down transformers. 2. We always use a multiple of 1.11 because for a pure sine wave the FORM FACTOR is the ratio of rms value of voltage or current with the avg. value of voltage or current and for pure sine wave rms value of current is Imax/root '2' and avg. value is 2Imax/pie and which comes out to be 1.11 so we cant have a combination of other then a multiple of 1.11.
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Related questions

Why electricity in India is in the multiples of 11 like 11kv, 22kv, 33kv ?

Description : Why electricity in India is in the multiples of 11 like 11kv, 22kv, 33kv ?

Last Answer : A:Transformer Induced voltage equation contains 4.44 factor. E -Induced emf per phase T -number of turns f -frequency Φ -maximum flux per pole From the equation we see that E is proportional to 4.4 and it is in turn multiple of 11.So always transmission voltage is multiple of 11

Why transmission line 11Kv OR 33KV, 66Kv not in 10kv 20kv?

Description : Why transmission line 11Kv OR 33KV, 66Kv not in 10kv 20kv?

Last Answer : Due to the form factor=1.11, so output voltage must be multiply of form factor, so we get 11, 22, 33 the answers mentioning the form factor 1.1 are correct. Just one clarification... 1.1 is ... available with terminal voltages from 10.5 kV to 15.5 kV so generation in multiples of 11 does not arise.

Why is transmission line 11kV, 33kV 66kV Not Is 10kV, 20kV, 30kV ?

Description : Why is transmission line 11kV, 33kV 66kV Not Is 10kV, 20kV, 30kV ?

Last Answer : 10kv plus to compensate losses in olden days 1kv were added and transmitted. Since all equipment used for transmission have a multiple of 11 from olden days, still that is being followed even though the losses are ... voltages, multiples of 11 is eazy for winding ratios.. i.e. 11kv to 33kv is 1:3.

Why Generation Voltage in Power Plant is Low (11kV to 33kV) ?

Description : Why Generation Voltage in Power Plant is Low (11kV to 33kV) ?

Last Answer : Generally electrical power is generated at low voltages (generation voltage will be around 11 to 33kV) depending on the power output rating of the generator and transmitted to the load centers by stepping up the ... operate at 23.5 kV with line currents of about 19,000 A at 0.85 power factor.

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Description : 44] The highest voltage for transmitting electrical power in India is A. 33kV B. 66kV C. 132kV D. 400kV

Last Answer : D. 400kv

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Description : High tension cables are generally used up to (a) 11kV (b) 33kV (c) 66 kV (d) 132 kV

Last Answer : (a) 11kV

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Description : For cost and safety, the outdoor substations are installed for voltages above (a) 11 kV (b) 33 kV (c) 60kV (d) 110kV

Last Answer : (b) 33 kV

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Last Answer : For 11kV line the inductance per km per phase will be of the order of: 1 mH

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Description : A load with an impedance of 440 ohms is connected across the secondary of the transformer illustrated. If the input voltage is 110 VAC and the step-up ratio is 10 to 1, what will be the primary current? EL-0055 A. 2.5 amps B. 25 amps C. 250 amps D. current cannot be determined with information given

Last Answer : Answer: B

A load is connected to the secondary of the transformer illustrated and the current through the load is 10 amps. If the step-up ratio is 10 to 1 and the input voltage is 110 VAC, what will be the current flow through the primary? EL-0055 A. 1 amp B. 10 amps C. 100 amps D. 1000 amps

Description : A load is connected to the secondary of the transformer illustrated and the current through the load is 10 amps. If the step-up ratio is 10 to 1 and the input voltage is 110 VAC, what will be the current flow through the primary? EL-0055 A. 1 amp B. 10 amps C. 100 amps D. 1000 amps

Last Answer : Answer: C

If the illustrated device has a step-up ratio of 10 to 1 what voltage be measured at the secondary shortly after the primary of the device is connected to 110 volts DC with a current of 12 amps? EL-0055 A. 0 volts B. 110 volts C. 1000 volts D. 1100 volts

Description : If the illustrated device has a step-up ratio of 10 to 1 what voltage be measured at the secondary shortly after the primary of the device is connected to 110 volts DC with a current of 12 amps? EL-0055 A. 0 volts B. 110 volts C. 1000 volts D. 1100 volts

Last Answer : Answer: A

In the illustrated circuit, if the input to leads 'B' and 'Y' was 24 VDC the output between 'A' and 'X' will be _________. EL-0069 A. 24 VDC B. 22.8 VDC, 24 VDC minus the 1.2 VDC voltage drop across two diodes C. undeterminable without knowing the turns ratio of the transformer D. 0 VDC

Description : In the illustrated circuit, if the input to leads 'B' and 'Y' was 24 VDC the output between 'A' and 'X' will be _________. EL-0069 A. 24 VDC B. 22.8 VDC, 24 VDC minus the 1.2 VDC voltage drop across two diodes C. undeterminable without knowing the turns ratio of the transformer D. 0 VDC

Last Answer : Answer: D

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Last Answer : Answer: D

In the illustration, if the device in figure 'A' has a step-up ratio of 10 to 1, what voltage should be measured at the secondary shortly after the primary of the device is connected to 110 volts DC? EL-0059 A. 0 volts B. 110 volts C. 11 volts D. 1100 volts

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Last Answer : Answer: A

Figure 'D' of the diagram shown in the illustration has a turns ratio of four to one. If a three-phase 440 volt supply is connected to terminals 'A-B-C', what voltage should develop across terminals 'a-b-c'? EL-0084 A. 64 volts B. 110 volts C. 190 volts D. 762 volts

Description : Figure 'D' of the diagram shown in the illustration has a turns ratio of four to one. If a three-phase 440 volt supply is connected to terminals 'A-B-C', what voltage should develop across terminals 'a-b-c'? EL-0084 A. 64 volts B. 110 volts C. 190 volts D. 762 volts

Last Answer : Answer: A

Figure 'C' of the diagram shown in the illustration has a turns ratio of four to one. If a three-phase 440 volt supply is connected to terminals 'A-B-C', what voltage should develop across terminals 'a-b-c'? EL-0084 A. 64 volts B. 110 volts C. 190 volts D. 762 volts

Description : Figure 'C' of the diagram shown in the illustration has a turns ratio of four to one. If a three-phase 440 volt supply is connected to terminals 'A-B-C', what voltage should develop across terminals 'a-b-c'? EL-0084 A. 64 volts B. 110 volts C. 190 volts D. 762 volts

Last Answer : Answer: C

Figure 'B' of the diagram shown in the illustration has a turns ratio of four to one. If a three-phase 440 volt supply is connected to terminals 'A-B-C', what voltage should develop across terminals 'a-b-c'? EL-0084 A. 64 volts B. 110 volts C. 190 volts D. 762 volts

Description : Figure 'B' of the diagram shown in the illustration has a turns ratio of four to one. If a three-phase 440 volt supply is connected to terminals 'A-B-C', what voltage should develop across terminals 'a-b-c'? EL-0084 A. 64 volts B. 110 volts C. 190 volts D. 762 volts

Last Answer : Answer: B

A load with an impedance of 440 ohms is connected across the secondary of the device illustrated. If the input voltage is 110 VAC and the step-up ratio is 10 to 1, what will be the primary current? EL-0055 A. 2.5 amps B. 25 amps C. 250 amps D. current cannot be determined with information given

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Last Answer : Answer: B

Figure 'A' of the diagram shown in the illustration has a turns ratio of four to one. If a three-phase 440 volt supply is connected to terminals 'A-B-C', what voltage should develop across terminals 'a-b-c'? EL-0084 A. 64 volts B. 110 volts C. 190 volts D. 762 volts

Description : Figure 'A' of the diagram shown in the illustration has a turns ratio of four to one. If a three-phase 440 volt supply is connected to terminals 'A-B-C', what voltage should develop across terminals 'a-b-c'? EL-0084 A. 64 volts B. 110 volts C. 190 volts D. 762 volts

Last Answer : Answer: B

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Description : A load is connected to the secondary of the device illustrated and the current through the load is 10 amps. If the step-up ratio is 10 to 1 and the input voltage is 110 VAC, what will be the current flow through the primary? EL-0055 A. 1 amp B. 10 amps C. 100 amps D. 1000 amps

Last Answer : Answer: C

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Which type of A.C motor is used in the fan (ceiling fan, exhaust fan, pedestal fan, bracket fan etc) which are find in the houses?

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How do we select a cable for a machine as per standards? Is there is any standard to select a cable as per voltage, or as per KVA and as per amps ratings?

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If we give 2334 A, 540V on Primary side of 1.125 MVA step up transformer, then what will be the Secondary Current, If Secondary Voltage=11 KV?

Description : If we give 2334 A, 540V on Primary side of 1.125 MVA step up transformer, then what will be the Secondary Current, If Secondary Voltage=11 KV?

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When voltage increases then current also increases then what is the need of over voltage relay and over current relay? Can we measure over voltage and over current by measuring current only?

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Last Answer : No. We can't sense the over voltage by just measuring the current only because the current increases not only for over voltages but also for under voltage (As most of the loads are non-linear in ... So, for a better protection of the system. It should have both over voltage & over current relay.

If we give 2334 A, 540V on Primary side of 1.125 MVA step up transformer, then what will be the Secondary Current, If Secondary Voltage=11 KV?

Description : If we give 2334 A, 540V on Primary side of 1.125 MVA step up transformer, then what will be the Secondary Current, If Secondary Voltage=11 KV?

Last Answer :  As we know the Voltage & current relation for transformer-V1/V2 = I2/I1 We Know, VI= 540 V; V2=11KV or 11000 V; I1= 2334 Amps. By putting these value on Relation540/11000= I2/2334 So,I2 = 114.5 Amps

When voltage increases then current also increases then why we need of over voltage relay and over current relay? Can we measure over voltage and over current by measuring current only?

Description : When voltage increases then current also increases then why we need of over voltage relay and over current relay? Can we measure over voltage and over current by measuring current only?

Last Answer : No. We cannot sense the over voltage by just measuring the current only because the current increases not only for over voltages but also for under voltage (As most of the loads are non-linear in ... , for a better protection of the system. It should have both over voltage & over current relay.

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Last Answer : Answer: B

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Last Answer : In Isolation transformer is used, if there is change in parameter values of any side, the other side parameters will remain unchanged.

For organizations who have threatening looking members stand in the background while the representative does an interview (Black Panthers, Taliban, ISIS, etc), how do they break the news to non threatening looking members that they can't be on TV despite their enthusiasm?

Description : For organizations who have threatening looking members stand in the background while the representative does an interview (Black Panthers, Taliban, ISIS, etc), how do they break the news to non threatening looking members that they can't be on TV despite their enthusiasm?

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Last Answer : Answer: B

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Last Answer : Answer: D

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Last Answer : Answer: A

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Last Answer : Answer: B

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Last Answer : Answer: C

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Description : In a three-phase, squirrel-cage type, induction motor the rotating magnetic field is established by the _____________. A. current induced in the rotor windings B. application of a three-phase voltage ... caused by the induced current in the squirrel-cage bars with the magnetic field of the stator

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Last Answer : Answer: A

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Description : The type of feature afforded auxiliaries vital to the operation of propelling equipment, where automatic restart after a voltage failure would not create a hazard, is termed _____________. A. low voltage protection B. high amperage protection C. low voltage release D. high amperage release

Last Answer : Answer: C