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which type of oil is use in transformers ?

which type of oil is use in transformers ?

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asked Aug 8, 2017 by anonymous

1 Answer

Answer :

Mineral oil is use in transformers .

answered Jan 10, 2018 by anonymous

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Related Questions

For large power transformers, self oil cooled type or air blast type which of the following values of current density may be used ? (a) 1.0 to 1.2 A/mm2 (b) 1.5 to 2.0 A/mm2 (c) 2.2 to 3.2 A/mm2 (d) 3.2 to 4.2 A/mm2

For large power transformers, self oil cooled type or air blast type which of the following values of current density may be used ? (a) 1.0 to 1.2 A/mm2 (b) 1.5 to 2.0 A/mm2 (c) 2.2 to 3.2 A/mm2 (d) 3.2 to 4.2 A/mm2
Last Answer : (c) 2.2 to 3.2 A/mm2

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asked Jun 23, 2021 by itszee

What are the safety features of oil filled transformers?

What are the safety features of oil filled transformers?
Last Answer : Environmental safety in case of spillage.There has to be a dyke wall for oil containment in case of spillage so that the oil does not get into ground / land.Oil level must be ... tested and minimum value must be maintained.Oil Cooling arrangement must be maintained.No leakage in radiators.

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asked Jan 15 by anonymous

Mention the properties of oil used in transformers.

Mention the properties of oil used in transformers.
Last Answer : The following are the desirable properties of transformer oil: -->It should be free from moisture --> It should have high dielectric strength --> It should have thermally stability and higher thermal conductivity -->It should be contaminated by temperature rise.

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asked Dec 27, 2021 by itszee

Why oil transformers are out door?

Why oil transformers are out door?
Last Answer : Oil fire point = 170 ºC easy catching of fire.

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asked Nov 17, 2021 by itszee

D. Loading of the transformers not i76 The changes in volume of transformer cooling oil due to variation of atmospeheric temperature during day and night is taken care of by which part of transformer? A. Conservator B. Breather C. Bushings D. Buchholz relay

76 The changes in volume of transformer cooling oil due to variation of atmospeheric temperature during day and night is taken care of by which part of transformer? A. Conservator B. Breather C. Bushings D. Buchholz relay
Last Answer : A. Conservator

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asked Jul 21, 2021 by jyoti kurekar

1] A Buchholz relay can be installed on A. Auto-transformers B. Air-cooled transformers C. Welding transformers D. Oil cooled transformers

1] A Buchholz relay can be installed on A. Auto-transformers B. Air-cooled transformers C. Welding transformers D. Oil cooled transformers

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asked Jul 17, 2021 by jyoti kurekar

A current density of _____ is ilsed for large power transformers with forced circulation of oil or with water cooling coils (a) 1.5 to 2.5 A/mm2 (b) 3.5 to 4.5 A/mm2 (c) 4.0 to 5.0 A/mm2 (d) 5.4 to 6.2 A/mm2

A current density of _____ is ilsed for large power transformers with forced circulation of oil or with water cooling coils (a) 1.5 to 2.5 A/mm2 (b) 3.5 to 4.5 A/mm2 (c) 4.0 to 5.0 A/mm2 (d) 5.4 to 6.2 A/mm2
Last Answer : (d) 5.4 to 6.2 A/mm2

12 views 1 answer

asked Jun 23, 2021 by itszee

The forced oil and air circulation method is usual one for transformers of capacities (a) upto 5 MVA (b) upto 10 MVA (c) upto 20 MVA (d) 30 MVA upwards

The forced oil and air circulation method is usual one for transformers of capacities (a) upto 5 MVA (b) upto 10 MVA (c) upto 20 MVA (d) 30 MVA upwards
Last Answer : (d) 30 MVA upwards

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asked Jun 23, 2021 by itszee

Natural oil cooling is used for transformers up to a rating of?

Last Answer : Natural oil cooling is used for transformers up to a rating of 3000 kVA.

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asked Mar 19, 2018 by anonymous

Core type transformers are popular in___________.

Core type transformers are popular in___________. (A) High voltage applications (B) Low voltage applications (C) All of the above (D) None of the above
Last Answer : Core type transformers are popular in High voltage applications

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asked May 8, 2018 by anonymous

the volt per turn of a certain single phase transformers is 1.7. the transformer has a step ratio of 3825/255volt. calculate the respective number of turns in each winding

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asked Aug 13, 2019 by Alacrity

How to connect Power transformers Lt panel

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asked Dec 20, 2018 by Harun

Give any two advantages of star-star connection in 3-ф transformers.

Last Answer : Advantages of star-star connection in 3-ф transformers: 1. It is possible to use the transformer for 3-phase, four wire system because of neutral. 2. The phase shift between primary and ... times line voltage, the no.of turns required for primary and secondary are less, hence economical.

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asked Sep 18, 2018 by anonymous

Classification of transformers

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Last Answer : Classification of transformers: Transformers are classified on the basis of core construction, frequency, and power. These are the three broad groups of transformers. a) Core construction ... Power transformers are used in conjunction with generators, 2. Distribution transformer

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asked Sep 16, 2018 by anonymous

Distribution transformers have good all day efficiency due to

Distribution transformers have good all day efficiency due to (A) low copper loss (B) low iron loss (C) low copper and iron loss (D) None of these
Last Answer : Distribution transformers have good all day efficiency due to low iron loss

162 views 1 answer

asked May 13, 2018 by anonymous

Which of the following connection of transformers will give highest value of secondary voltage ?

Which of the following connection of transformers will give highest value of secondary voltage ? (A) Delta primary delta secondary (B) Delta primary star secondary (C) Star primary star secondary (D) Star primary delta secondary
Last Answer : Which of the following connection of transformers will give highest value of secondary voltage ? (A) Delta primary delta secondary (B) Delta primary star secondary (C) Star primary star secondary (D) Star primary delta secondary

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asked May 8, 2018 by anonymous

Two transformers A and B having equal outputs and voltage ratios but unequal percentage

Two transformers A and B having equal outputs and voltage ratios but unequal percentage impedances of 4 and 2 are operating in parallel. The transformer A will be overloaded by
Last Answer : Two transformers A and B having equal outputs and voltage ratios but unequal percentage impedances of 4 and 2 are operating in parallel. The transformer A will be overloaded by 33%

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asked May 8, 2018 by anonymous

The friction losses in Real Transformers are :

The friction losses in Real Transformers are : (A) 0% (B) 5% (C) 25% (D) 50%
Last Answer : A

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asked May 8, 2018 by anonymous

Two 3-phase transformers cannot be operated in parallel, if their :

Two 3-phase transformers cannot be operated in parallel, if their : (A) kVAs are different (B) phase sequences are different (C) % impedances are different (D) voltage ratios are different
Last Answer : Two 3-phase transformers cannot be operated in parallel, if their : phase sequences are different

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asked Apr 30, 2018 by anonymous

Which of the following is the advantage of using CRGO steel in transformers?

Which of the following is the advantage of using CRGO steel in transformers? A) High magnetic flux density B) Low permeability C) Both A and B D) None of these
Last Answer : It definitely High Magnetic Flux Density since a crgo steel has always a more around 3% of silicon proportion among the remaining ferrite which make cold rolled grain oriented steel having high flux magnetic ... for more about the crgo core you can learn here https://nicoreindia.com/crgo-core/

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asked Apr 29, 2018 by anonymous

Two transformers having the same p.u. impedance connected in parallel share the connected load

Two transformers having the same p.u. impedance connected in parallel share the connected load (A) equally (B) in proportion to the respective ratings (C) in proportion to the voltage ratio (D) in proportion to the zero phase displacement
Last Answer : Two transformers having the same p.u. impedance connected in parallel share the connected load in proportion to the respective ratings

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asked Apr 25, 2018 by anonymous

Non -loading heat run test on transformers is performed by means of

Non -loading heat run test on transformers is performed by means of
Last Answer : Non -loading heat run test on transformers is performed by means of Sumpner's test

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asked Apr 25, 2018 by anonymous

Consider the following statements regarding three-phase transformers in Open -Delta (V -V) connections

Consider the following statements regarding three-phase transformers in Open -Delta (V -V) connections : 1. Being a temporary remedy when one transformer forms of Delta -Delta system is &imaged, and removed from service. ... and 2 only (b) 1 and 3 only (c) 2 and 3 only (d) 1, 2 and 3
Last Answer : Consider the following statements regarding three-phase transformers in Open -Delta (V -V) connections : 1. Being a temporary remedy when one transformer forms of Delta -Delta system is &imaged, and removed from service. ... and 2 only (b) 1 and 3 only (c) 2 and 3 only (d) 1, 2 and 3

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asked Apr 25, 2018 by anonymous

In potential transformers, the secondary turns are increased slightly and the primary and secondary windings...

In potential transformers, the secondary turns are increased slightly and the primary and secondary windings are wound as closely as possible to compensate for (a) Phase angle and ratio error, ... loss and hysteresis loss, respectively (d) The hysteresis loss and eddy current loss, respectively
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asked Apr 25, 2018 by anonymous

Regulating transformers are used in power systems for control of :

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asked Apr 14, 2018 by anonymous

In large capacity transformers, 5% of the turns at the end of hv winding are provided with extra insulation so...

In large capacity transformers, 5% of the turns at the end of hv winding are provided with extra insulation so as to provide protection (1) against corona (2) against lightning (3) due to surges occurring during switching operation (4) All of these

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asked Apr 10, 2018 by anonymous

Distribution transformers have core losses:

Distribution transformers have core losses: (1) More than full load copper losses (2) Equal to full load copper losses (3) Less than full load copper losses (4) W Negligible compared to full load copper losses
Last Answer : Distribution transformers have core losses: Less than full load copper losses.

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asked Apr 9, 2018 by anonymous

Three single phase transformers are connected in delta-delta to step down a line voltage of 138 kV to...

Three single phase transformers are connected in delta-delta to step down a line voltage of 138 kV to 4160 V to supply power to a production plant. The plant draws 21 MW at a lagging power factor of 86 %. Calculate the apparent power ... HV line. (A) 24.4 MVA (B) 48.8 MVA (C) 12.2 MVA (D) 6.1 MVA

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asked Apr 5, 2018 by anonymous

What is the back EMF in Transformers?

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asked Mar 15, 2018 by anonymous

of what use are current and voltage transformers in protective systems

Last Answer : Current transformers (CT) : Current transformer (CT) actually step down the high current to low current for the operation of relays. Current transformer is use for measurement of ... use for relay. This is about potential transformer.

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asked Jan 15, 2018 by James

Is Doble Testing valid on "Dry Type" transformers What is ANSI or IEEE 's opinion?

Is Doble Testing valid on "Dry Type" transformers What is ANSI or IEEE 's opinion?
Last Answer : Refer this url to know about IEEE/ANSI

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asked Jan 14 by anonymous

Routine maintenance of dry-type transformers should include ______________. A. preventing the entrance of water from broken pipe lines steam lines B. keeping protective surfaces and insulating bushings free of dirt and conductive debris C. periodic testing of insulation resistance with a megger D. all of the above

Routine maintenance of dry-type transformers should include ______________. A. preventing the entrance of water from broken pipe lines steam lines B. keeping protective surfaces and insulating bushings free of ... debris C. periodic testing of insulation resistance with a megger D. all of the above
Last Answer : Answer: D

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asked Jan 4 by itszee

Routine maintenance of dry-type transformers should include ____________. A. cleaning the windings, if accessible, with a vacuum cleaner or very low pressure air B. measuring and recording the winding temperature with an accurate mercury thermometer C. periodic cleaning of the winding insulation with an approved solvent D. making sure that the units are close to bulkheads or corners to protect them from damage

Routine maintenance of dry-type transformers should include ____________. A. cleaning the windings, if accessible, with a vacuum cleaner or very low pressure air B. measuring and recording the winding ... . making sure that the units are close to bulkheads or corners to protect them from damage
Last Answer : Answer: A

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asked Jan 4 by itszee

What are the advantages of shell type transformer over core type transformers?

What are the advantages of shell type transformer over core type transformers?
Last Answer : In shell type transformers the coils are well supported on the all sides and so they can withstand higher mechanical stresses developed during short circuit conditions. Also the leakage reactance will be less in shell type transformers.

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asked Dec 27, 2021 by itszee

State the type transformers?

State the type transformers?
Last Answer : Transformers can be classified into different groups and types based on the following factors. 1. Type of core. a. Core type transformer core. b. Shell type transformer core. c. ... Auto transformer. b. Potential transformer (instrument transformer). c. Current transformer (instrument transformer).

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asked Nov 15, 2021 by itszee

Helical windings are used in (a) distribution transformers (b) power transformers (c) shell type transformers (d) none of the above

Helical windings are used in (a) distribution transformers (b) power transformers (c) shell type transformers (d) none of the above
Last Answer : (b) power transformers

9 views 1 answer

asked Jun 23, 2021 by itszee

Why should Dry-Type Transformers never be overloaded?

Why should Dry-Type Transformers never be overloaded?
Last Answer : Overloading of a transformer results in excessive temperature. This excessive temperature causes overheating which will result in rapid deterioration of the insulation and cause complete failure of the transformer coils.

15 views 1 answer

asked Apr 3, 2021 by anonymous

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