The efficiency of two identical transformers under load conditions can be determined by?

Question

Please Log in or Register for more.

The efficiency of two identical transformers under load conditions can be determined by?

322 views

asked Mar 19, 2018 by anonymous

1 Answer

Please log in or register to answer this question.

Related Questions

An ideal transformer will have maximum efficiency at a load such that?

Last Answer : An ideal transformer will have maximum efficiency at a load such that copper loss equal to iron loss.

204 views 1 answer

asked Mar 19, 2018 by anonymous

For a transformer, operating at constant load current, maximum efficiency will occur at?

For a transformer, operating at constant load current, maximum efficiency will occur at?
Last Answer : For a transformer, operating at constant load current, maximum efficiency will occur at unity power factor.

124 views 1 answer

asked Mar 19, 2018 by anonymous

A transformer operates 24 hours day at full -load. It's full -load efficiency is :

A transformer operates 24 hours day at full -load. It's full -load efficiency is : (A) equal all day efficiency (B) more than all -day efficiency (C) less than all -day efficiency (D) equal to maximum efficiency
Last Answer : A transformer operates 24 hours day at full -load. It's full -load efficiency is : equal all day efficiency

264 views 1 answer

asked Apr 30, 2018 by anonymous

Generators for peak load plants are usually designed for maximum efficiency at?

Last Answer : Generators for peak load plants are usually designed for maximum efficiency at 50 to 75 percent full load.

138 views 1 answer

asked Mar 20, 2018 by anonymous

The secondary of a current transformer is always short-circuited under operating conditions because it?

The secondary of a current transformer is always short-circuited under operating conditions because it?
Last Answer : The secondary of a current transformer is always short-circuited under operating conditions because it avoids core saturation and high voltage induction.

107 views 1 answer

asked Mar 19, 2018 by anonymous

Distribution transformers are generally designed for maximum efficiency around?

Last Answer : Distribution transformers are generally designed for maximum efficiency around 50% load.

142 views 1 answer

asked Mar 19, 2018 by anonymous

Power transformers are generally designed to have maximum efficiency around?

Last Answer : Power transformers are generally designed to have maximum efficiency around near full-load.

106 views 1 answer

asked Mar 19, 2018 by anonymous

Three identical resistors connected in star consume 5000 W. If the resistors are connected in

Three identical resistors connected in star consume 5000 W. If the resistors are connected in delta across the same supply, the power consumed will be
Last Answer : Three identical resistors connected in star consume 5000 W. If the resistors are connected in delta across the same supply, the power consumed will be 15000 W

185 views 1 answer

asked May 8, 2018 by anonymous

The direction of rotation of an hysteresis motor is determined by?

Last Answer : The direction of rotation of an hysteresis motor is determined by position of shaded pole with respect to main pole.

230 views 1 answer

asked Mar 20, 2018 by anonymous

74)Power transformers are generally designed to have maximum efficiency around A. No load B. Half load C. Near full load D. 10% overload

74)Power transformers are generally designed to have maximum efficiency around A. No load B. Half load C. Near full load D. 10% overload
Last Answer : C. Near full load

14 views 1 answer

asked Jul 21, 2021 by jyoti kurekar

In a D.C. shunt motor, under the conditions of maximum power, the current in the armature will be?

Last Answer : In a D.C. shunt motor, under the conditions of maximum power, the current in the armature will be more than full-load current.

366 views 1 answer

asked Mar 20, 2018 by anonymous

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.

158 views 1 answer

asked Mar 19, 2018 by anonymous

What will happen if the transformers working in parallel are not connected with regard to polarity ?

Last Answer : Winding will be damaged

135 views 2 answers

asked Mar 19, 2018 by anonymous

If the percentage impedances of the two transformers working in parallel are different, then?

If the percentage impedances of the two transformers working in parallel are different, then?
Last Answer : If the percentage impedances of the two transformers working in parallel are different, then parallel operation will still be possible, but the power factors at which the two transformers operate will be different from the power factor of the common load.

130 views 1 answer

asked Mar 19, 2018 by anonymous

Two transformers do not have equal percentage impedance. This is likely to result in?

Two transformers are connected in parallel. These transformers do not have equal percentage impedance. This is likely to result in?
Last Answer : Two transformers are connected in parallel. These transformers do not have equal percentage impedance. This is likely to result in loading of the transformers not in proportion to their kVA ratings.

377 views 1 answer

asked Mar 19, 2018 by anonymous

Short circuit test on transformers is conducted to determine?

Last Answer : Short circuit test on transformers is conducted to determine copper losses.

218 views 1 answer

asked Mar 19, 2018 by anonymous

For the parallel operation of single phase transformers it is necessary that they should have?

Last Answer : Necessary conditions required to be satisfied in order to ensure successful parallel operation of single phase transformers: 1. Only transformers having the same phase displacement between primary and secondary ... . 7. The phase sequence must be followed strictly on HV and LV side connection.

196 views 2 answers

asked Mar 19, 2018 by anonymous

Natural air cooling is generally restricted for transformers up to?

Last Answer : Natural air cooling is generally restricted for transformers up to 1.5 MVA .

187 views 1 answer

asked Mar 19, 2018 by anonymous

Losses which occur in rotating electric machines and do not occur in transformers are?

Losses which occur in rotating electric machines and do not occur in transformers are?
Last Answer : Friction losses windage losses

208 views 2 answers

asked Mar 19, 2018 by anonymous

The efficiencies of transformers compared with that of electric motors of the same power are?

The efficiencies of transformers compared with that of electric motors of the same power are?
Last Answer : Transformers have high efficiency than the same ratted motors

179 views 2 answers

asked Mar 19, 2018 by anonymous

Explain the concept of initial and final conditions in switching for L and C.

Explain the concept of initial and final conditions in switching for L and C.
Last Answer : i) Inductor: The current through an inductor cannot change instantly. If the inductor current is zero just before switching, then whatever may be the applied voltage, just after switching the inductor ... open-circuit. The initial and final conditions are summarized in following table:

466 views 1 answer

asked Sep 7, 2018 by anonymous

The efficiency of a transformer, under heavy loads, is comparatively low because?

The efficiency of a transformer, under heavy loads, is comparatively low because?
Last Answer : The efficiency of a transformer, under heavy loads, is comparatively low because copper loss becomes high in proportion to the output.

113 views 1 answer

asked Mar 19, 2018 by anonymous

State why a transformer always have an efficiency of more than 90%.

State why a transformer always have an efficiency of more than 90%.
Last Answer : As transformer is static device with no moving parts, the losses due to friction & windage are completely absent. Hence transformer has efficiency of more than 90%.

262 views 1 answer

asked May 22, 2020 by anonymous

Efficiency of a power transformer is of the order of?

Last Answer : The efficiency of a power transformer is of the order of 98 percent.

99 views 1 answer

asked Mar 19, 2018 by anonymous

[23] Transformers are rated in KVA instead of KW because A. load power factor is often not known B. KVA is fixed whereas KW depends on load power factor C. Total transformer loss depends on volt ampere D. It has become customary

[23] Transformers are rated in KVA instead of KW because A. load power factor is often not known B. KVA is fixed whereas KW depends on load power factor C. Total transformer loss depends on volt ampere D. It has become customary
Last Answer : C. Total transformer loss depends on volt ampere

130 views 1 answer

asked Jul 21, 2021 by jyoti kurekar

In an actual transformer the iron loss remains practically constant from no load to full load because?

In an actual transformer the iron loss remains practically constant from no load to full load because?
Last Answer : In an actual transformer the iron loss remains practically constant from no load to full load because core flux remains practically constant.

113 views 1 answer

asked Mar 19, 2018 by anonymous

Negative voltage regulation is indicative that the load is?

Negative voltage regulation is indicative that the load is?
Last Answer : Negative voltage regulation is indicative that the load is capacitive.

228 views 1 answer

asked Mar 19, 2018 by anonymous

In a given transformer for a given applied voltage, losses which remain constant irrespective of load changes are?

In a given transformer for a given applied voltage, losses which remain constant irrespective of load changes are?
Last Answer : In a given transformer for a given applied voltage, losses which remain constant irrespective of load changes are hysteresis and eddy current losses.

152 views 1 answer

asked Mar 19, 2018 by anonymous

The maximum load that a power transformer can carry is limited by its?

The maximum load that a power transformer can carry is limited by its?
Last Answer : The maximum load that a power transformer can carry is limited by its voltage ratio.

133 views 1 answer

asked Mar 19, 2018 by anonymous

Minimum voltage regulation occurs when the power factor of the load is?

Minimum voltage regulation occurs when the power factor of the load is?
Last Answer : Minimum voltage regulation occurs when the power factor of the load is leading.

221 views 1 answer

asked Mar 19, 2018 by anonymous

In a step-down transformer, there is a change of 15 A in the load current. This results in change of supply current of?

In a step-down transformer, there is a change of 15 A in the load current. This results in change of supply current of?
Last Answer : In a step-down transformer, there is a change of 15 A in the load current. This results in change of supply current of less than 15A.

156 views 1 answer

asked Mar 19, 2018 by anonymous

5 The efficiency of a transformer is maximum when A. It runs at half full load B. it runs at full load C. its Cu loss equal iron loss D. it runs over load

5 The efficiency of a transformer is maximum when A. It runs at half full load B. it runs at full load C. its Cu loss equal iron loss D. it runs over load
Last Answer : C. Its cu loss equal iron loss

18 views 1 answer

asked Jul 21, 2021 by jyoti kurekar

A common method of cooling a power transformer is?

Last Answer : A common method of cooling a power transformer is oil cooling.

156 views 1 answer

asked Mar 19, 2018 by anonymous

Harmonics in transformer result in?

Last Answer : Harmonics in transformer result in increased core losses, increased I2R losses, and magnetic interference with communication circuits.

70 views 1 answer

asked Mar 19, 2018 by anonymous

TRANSFORMERS MCQ

TRANSFORMERS MCQ
Last Answer : 101. A shell-type transformer has (a) high eddy current losses (b) reduced magnetic leakage (c) negligibly hysteresis losses (d) none of the above Ans: b 102. A transformer can have regulation closer to zero (a ... (6) much smaller (c) much higher (d) somewhat smaller (e) none of the above Ans: c

537 views 3 answers

asked Jun 22, 2021 by itszee

What are the schedules of maintenance done on transformers?

What are the schedules of maintenance done on transformers?
Last Answer : Ans. Following are the schedules of maintenance on transformers. a. Daily maintenance. b. Monthly maintenance. c. Quarterly maintenance. d. Half yearly maintenance. e. Yearly maintenance. f. 5 Yearly maintenance.

7 views 1 answer

asked Jun 20, 2021 by itszee

Why a transformer requires cooling. What are the methods of cooling transformers?

Why a transformer requires cooling. What are the methods of cooling transformers?
Last Answer : Ans. Transformers requires cooling as they get heated up due to various losses taking place in the transformer. (like iron of copper losses) Following are the methods of cooling of transformer. a. Natural ... . Forced oil air Natural Cooling (OFAN). d. Forced oil and forced Air cooling (OFAF).

6 views 1 answer

asked Jun 20, 2021 by itszee

What are the loses in Transformers, Explain?

What are the loses in Transformers, Explain?
Last Answer : Ans. (1) Iron loses (2) Copper loses Iron Loss : Iron loss occurs in the transformers Iron core due to hysteresis and eddy currents taking place. They are almost fixed irrespective of ... losses in the primary and the secondary windings of the transformer which with the loading of transformer.

3 views 1 answer

asked Jun 20, 2021 by itszee

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

63 views 0 answers

asked Aug 13, 2019 by Alacrity

Classify the transformers based on the construction, frequency and power.

Classify the transformers based on the construction, frequency and power.
Last Answer : Classification of Transformer Based On: i) Construction: Shell type, Core type, Berry type ii) Change in voltage level: Step-Up, Step-Down, iii) Number of phases: Single phase, Three phase iv) ... Control vi) Cooling: Self-cooled, Air-cooled, Forced-air cooled, Oil-cooled, Forced-oil cooled.

133 views 1 answer

asked Aug 30, 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

578 views 1 answer

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%

671 views 1 answer

asked May 8, 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

96 views 1 answer

asked May 8, 2018 by anonymous

In a transmission line if booster transformers are to be used, preferred location will be

In a transmission line if booster transformers are to be used, preferred location will be (A) At the receiving end (B) At the sending end (C) At the intermediate point (D) Anywhere in the line
Last Answer : In a transmission line if booster transformers are to be used, preferred location will be At the intermediate point

346 views 1 answer

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

3.3k views 2 answers

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

150 views 1 answer

asked Apr 30, 2018 by anonymous

An additional condition for parallel operation of three-phase transformers over single-phase transformers is that

An additional condition for parallel operation of three-phase transformers over single-phase transformers is that
Last Answer : An additional condition for parallel operation of three-phase transformers over single-phase transformers is that the transformers should belong to the same vector group

144 views 1 answer

asked Apr 29, 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/

153 views 2 answers

asked Apr 29, 2018 by anonymous

Instrument transformers are?

Last Answer : Instrument transformers are potential transformers, current transformers.

84 views 1 answer

asked Mar 21, 2018 by anonymous

What is the back EMF in Transformers?

77 views 0 answers

asked Mar 15, 2018 by anonymous

anonymous · Answer 1 · 2018-03-19T20:19:08+0000

The efficiency of two identical transformers under load conditions can be determined by back-to-back test.

The efficiency of two identical transformers under load conditions can be determined by?

Please log in or register to add a comment.

1 Answer

Answer :

Please log in or register to add a comment.

Please log in or register to answer this question.

Related Questions