x

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

180 views

2 Answers

Answer :

The efficiencies of transformers compared with that of electric motors of the same power are somewhat smaller.
Like 0 like

Answer :

Transformers have high efficiency than the same ratted motors
Like 0 like

Please log in or register to answer this question.

Related Questions


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

Show More

211 views 2 answers



Suggest electric motors for i) traction ii) crane iii) lathe machine iv) domestic fan.
Last Answer : i) Traction :- DC Series motor  ii) Crane :- DC Series motor  iii) Lathe machine :- 3 phase Induction motor or DC shunt motor  iv) Domestic fan :- 1 phase induction motor

Show More

77 views 1 answer



State which electric motors are generally used in electro agro systems with reason.
Last Answer : 1) 3 phase induction motor is used in electro agro system for water pumping from wells as 3 phase ac supply is easily available, cost of induction motor is less, maintenance free being rugged ... as 1 phase ac supply is easily available for domestic purpose, repair is simple and easily available.

Show More

95 views 1 answer



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. 

Show More

133 views 1 answer




Last Answer : The standard full-load power factor ratings for synchronous motors are unity or 0.8 leading.

Show More

99 views 1 answer




Last Answer : For power factor correction, synchronous motors operate at no-load and greatly over-excited fields.

Show More

110 views 1 answer




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

Show More

108 views 1 answer




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

Show More

159 views 1 answer



138 views 2 answers



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.

Show More

135 views 1 answer




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

Show More

144 views 1 answer



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.

Show More

381 views 1 answer




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

Show More

221 views 1 answer




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.

Show More

201 views 2 answers




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

Show More

191 views 1 answer



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

Show More

325 views 1 answer



Electric Power
Last Answer : Electric Power

Show More

95 views 1 answer



State elements of diesel electric power plant with their functions. 
Last Answer : Elements of Diesel Power Plant with their function):   1) Diesel Engine: - This is the main component of the P.P. which develops mechanical power. 2) Engine air intake system: - Air ... fuel as per requirement. 10) Alternator: - Its function is to convert mechanical power into electrical power.

Show More

100 views 1 answer



Options: A) WATT B) AMPERE C) VOLTS D) OHM
Last Answer : Correct Answer: A) WATT

Show More

76 views 1 answer



Electric power formula
Last Answer : Electric power formula

Show More

65 views 1 answer



"Hydro electric power station are not perennial power station". Justify.
Last Answer : Justification: The water utilized by the hydro power plants comes mostly from storage dams/reservoirs which get filled up during the monsoon rainy season. Such reservoirs are utilized for supplying ... are important. Hence "Hydro electric power stations are not perennial power station" 

Show More

92 views 1 answer



Explain starting system in diesel electric power plant.
Last Answer : Starting system in Diesel Electric Power Plant: It includes Storage battery, compressed air tanks, self-starter etc. The purpose of engine starting system is to rotate the engine initially while ... as Ammeters, Voltmeters, Wattmeters, Thermometers, Pressure gauges, Visible and audible alarm etc.

Show More

130 views 1 answer



Explain fuel system and air intake system in diesel electric power plant.
Last Answer : Fuel system and air intake system in diesel electric power plant :  Fuel system: It consists of storage tank, strainers, fuel transfer pump and all day fuel tank. The fuel oil is supplied ... Filters are provided to remove dust particles from air which may act as abrasive in the engine cylinder.

Show More

125 views 1 answer



State any four advantages and four disadvantages of diesel electric power plant. 
Last Answer : Advantages of Diesel electric power plant:- 1) The design and layout of Diesel electric power plant is simple. 2) It requires less space. 3) Time required for complete erection of diesel power plant is less ... . 9) The useful life is very short. 10) Availability of fuel in future may be limited.

Show More

125 views 1 answer



List out the four applications of diesel electric power plant.
Last Answer : Applications of Diesel Power Plant: 1. It can be used as a standby (emergency) power plant to maintain continuity of supply. (Incase failure of main supply like hospital, Telephone exchange Radio stations, ... 10. Diesel plants are widely used for generating power ranging from 100 to 5,000 H.P.

Show More

169 views 1 answer



An _____________is a network of electrical components used to supply, transfer and use electric power:  (A) Electric power system (B) Electric power (C) All of the above (D) None of the above
Last Answer : An Electric power system is a network of electrical components used to supply, transfer and use electric power.

Show More

94 views 1 answer



The storage battery generally used in electric power stations is  (1) zinc carbon battery (2) lead acid battery (3) nickel cadmium battery (4) lithium -ion battery
Last Answer : The storage battery generally used in electric power stations is lead acid battery 

Show More

107 views 1 answer



Power factor of electric bulb is?
Last Answer : Power factor of electric bulb is unity.

Show More

93 views 1 answer




Last Answer : Power for lighting in passanger coach, in a long distance electric train, is provided through individual generator of bogie and batteries.

Show More

103 views 1 answer




Last Answer : In a steam locomotive electric power is provided through small turbo-generator.

Show More

78 views 1 answer




Last Answer : The power mentioned on the name plate of an electric motor indicates the output power available at the shaft.

Show More

97 views 1 answer



215 views 2 answers



What is electric power generation transmission and distribution?
Last Answer : Generation: it wrong word at here.because it is no generation it is conversion of one form of energy into electrical form.it may by using any type of energy. Transmission is just to ... place to other by providing some modifications And distribution means use of this energy for any purpose.

Show More

216 views 1 answer



what are the three different types of Electric power?
Last Answer : Real,reactive,apparent power

Show More

126 views 2 answers



Choose the correct order of electric discharge lamps in their increasing order of efficiencies (lumens/watt) :  (A) Sodium vapour lamp, Mercury vapour lamp, Neon lamp  (B) Neon lamp, Sodium vapour ... Mercury vapour lamp, Sodium vapour lamp  (D) Mercury vapour lamp, Sodium vapour lamp, Neon lamp
Last Answer : Choose the correct order of electric discharge lamps in their increasing order of efficiencies (lumens/watt) :  (A) Sodium vapour lamp, Mercury vapour lamp, Neon lamp  (B) Neon lamp, Sodium ... Mercury vapour lamp, Sodium vapour lamp  (D) Mercury vapour lamp, Sodium vapour lamp, Neon lamp

Show More

95 views 1 answer




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

Show More

157 views 1 answer



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

Show More

14 views 1 answer



[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

Show More

132 views 1 answer



3 phase motor  42 hp  same ratting two motors  but pole change 2 and 4 pole   tell me difference amp of both motors

Show More

2.6k views 0 answers




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

Show More

71 views 1 answer



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

Show More

547 views 3 answers



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.

Show More

7 views 1 answer



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).

Show More

7 views 1 answer



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.

Show More

3 views 1 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
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

Show More

587 views 1 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 
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%

Show More

686 views 1 answer



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

Show More

99 views 1 answer



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

Show More

348 views 1 answer



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

Show More

3.3k views 2 answers


Show More⇦ PreviousNext ⇨