ee question ram

7/29/2019 Ee Question Ram

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1. What is the power ratio between power in Star and Delta circuit?

2. What is the difference between earth and neutral

3. What is the difference between Earthing & grounding

4. What is a u.p.s

5. At what condition a synchronous motor acts as a synchronous condenser?

6. How is a 100 MVA transformer cooled?

7. What is the instantaneous value of voltage in a 3-phase balanced star

connected circuit?

8. What is the difference between regulator and stabiliser

9. Whats happens when we give DC to a induction motor?

10.Describe How energy is stored in a inductor on electronic level

11.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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12.Is it possible for a feedback surge to travel over a wireless connection? Would

the answer be different in a vacuum?

13.What is the voltage drop for 100kw motor if the length of the cable is 200m

and what is the cable size.14.What is the different between CGS system and MKS system?

15.How to Simulate an Induction motor?

16.When there is a sudden loss in the demand what happens to the transformer

and generation?

17.How do you measure the leakage current in a house wiring?

18.What are the technical reasons for soaking transformers for various times

before allowing them to pick load after a fault or maintenance outage or as a

new installation.

19.When we connect the capacitor Banks in Series with the circuit

20.Why is the transformer rated in KVA?

21.What is the function of a choke in tube light?

22.How do you detect the exact location of a cable fault if its cable puncture

23.When we increase load , current drawn from source also increases why ?

24.What is the reason of power development in synchronous generator due to

saliency ?

25.What is the purpose of calculating knee point voltage for Current

transformers?


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26.What will happen if we apply dc volt across transformer?

27.Is possible to increase the voltage without using transformer? Why?28.Why less loss occurs when we use DC supply than AC supply?

29.Earth has the constant potential so we take it as reference.but in steo &

touch voltage we use to calculate

30.Why Transistors are not used as switching devices?

31.What is watt?

32.In a synchronous motor armature current flows due to revolving flux which in

turn rotates the load, but in no load condition armature current is zero hence

there is no revolving flux then how motor rotates?

33.Does HVDC mode of transmission has an economic advantage over EHV-AC

transmission. Justify

34.Why we are using Sinusidol wave in all electrical systems?

35.Why the generators are made such that they generate only sinusoidal wave?


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36. What is the voltage that is supplied to the electric traction trains?

37.What is DIV? What does 100V/DIV or 50A/DIV mean?

38.How to find the terminals in SCR? Also in BC327 transistor?

39.What is induction motor?

40.What is a Transducer?

41.What is the use of SCOTT connections?

42.What is the difference between P,PI,PID CONTROLLER?

43.What is Synchronous condenser ?

44.How much should be the insulation resistance value of a 5KW motor and

50KW motor?

45.Why we cannot use the capacitive load?

46.What is the purpose of coupling capacitor?

47.What is the purpose of Q-point in transistor?

48.What is meaning by the SKIN effect in electrical circuits


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49.Why are we employing star type transformer at transmission end and delta

type transformer at receiving end?

50.What is difference between potentiometer and rheostat?

51.What is the value of reflection co-efficient of tranmission line having VSWR?

52.What is a DSM(Demand Side Management)?.

53.What is the main Electrical IS rules?.

54.How much voltage is present in neutral resistance? And how much voltage is

present in earth resistance

55.What is the resistance between neutral and earth.

56.What is Particle Swam Optimisation?

57.What is the effect of pole slipping in generator and how it will slip?

58.What is signal?

59. What is Gsm?

60.What about AMPS?

61.What EDGE?


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62.What is GPRS?

63. What is Ciphering?

64.Difference Between Noise and Attenuation?

65.Explain the operation of a transistor

66.What is the use of control panels in transmission systems?

67.What is the flyback convertor?

68.What do you mean by traction system, What type of traction system is used

in electric train

69.How snubber circuit works to protect switching devices?

70. What is the difference between AC choke (inductor) and DC choke

(inductor),

working and design point of view?


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71.Why secondary of open delta pt (two element pt) centre tap is earthed? What

happen when this earth is removed?

72.Alternators are invariably star connected why?

73.What is the difference between SSR drive& AC drive?

74. What will be change in programming when we use 5/3 solenoid in place of

5/2 in operating of a cylinder?

75. What is isolation Transformer?

76. Why battery is connected in series?

77. Why Transformer in KVA?

78. What is function of pump in DG?

79.why DG neutral is earth?

80.What is the principle of high speed direct drive motor ?

81. Can we load Power capacitors on DG sets?


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82. What are the factors required for selection of transformer rating?

83.Why the frequency is 50 hz in india.can we use some other frequency.if sowhat is the range and what will be the effect in present power system if we

change the frequency as you suggest ?

84.Consider a 415v/200v step down transformer.can we use use it as step up

transformer by giving 200v in secondary and taking output from primary?

85.What is the maximum genarating voltage in india?

86.How power cable & control cable can be differentiate from each other?

87. We have one ups its neutral is not earthed. Its one distribution MCB has a

earth fault .but we can not put off any MCB. So how to find out that in which

circuit is earthed without isolating the breaker?

88.WHAT IS THE MEANING OF KEY SINGLE LINE DIAGRAM

89.What is the meaning of rms value?

90.What is derating factor in Cable ? How we minimise this?


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91. How we can calculate the transformer size?

92.How VFD(variable frequency) drive is used as a energy saver....?

93.What is effect of unbalanced load -- say R 15A, Y 25A, B ?

94.If i want to build 230kv substation what are the equipments to be installed?

95.How power saving takes place through VFD?

96.How to write program by ladder logic in case of PLC operation?

97.What is surge suppressor?

98. How to find transformer is in normal position? Whether its in charged

condition or not? Except humming sound?

99.How to find motor contactor rating and bimetalic relay rating? Of 30kw motor

which will operate on star-delta starter?


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100. How to calculate the capacitor range for load for pf improvement?

Example

for 65 hp load how to calculate capacitor range?

101. As all us know that the capacitor panel is connected to improve the

power factor when it is PF is low. Whether we can connect the capacitor

panel on D.G. side? If it is yes why?

102. Why voltage drop will occur in 3 phase line?

103. How a generator is positioned in a hydroelectric power plant?

104. What is the generating voltage of a power station consided generally?

105. How to control the generator output voltage? What r the condition

should satisfy for synchronization?

106. What is inrush current in transformer?

107. Why making capacity is more than breaking capacity?

108. What is cathodic protection in Tank, and product pipelines?

109. Can you give main difference between ELCB And RCCB?

110. What is GD2(kg-m2) for Sq. Cage ind. Motor?

111. What is the difference between earthed and unearthed cable

112. What are the difference between C-Curve and D-Curve for MCB's.

113. How to select a CT


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114. How to select a circuit breaker

115. What r the advantage of selecting micro controller type tripping of

circuit

breaker than relay type tripping?116. What is the meaning of BUS?

117. In step down transformer (415/200V),mistakenly secondary side is

connected to 415V for some hours, what would be result of this condition?

118. What is the difference between negative dc voltage and positive dc

voltage because some circuit uses -24,-5,-12,- 15,volt dc

119. If any lead acid battery is having low or high sp.gravity then what will

be

effect of battery and why?

120. In Aeroplane what circuitry or method use for earthing?

121. What is the diff. Between two phase & three phase supply?

122. What is the reason for balance of voltage in magnetic balance test?

123. How can we measure and monitor critical performance parameters of

Diesel

Generator Sets, both electrical and engine ?

124. How can you prove that in CE configuration a transistor has 180

degree phase shifted output ?

125. What do you mean by 1 ton in AC`s?

126. Procedure for conducting vector group test on power transformers.why

it is conducted? How to increase the specific gravity of DG batteries

127. What is mean CT Saturation? How to calculate?


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128. There are 2 Flip_Flop with logic between them. Given Clock to Q delay,

logic prop. Delay, set up and hold times specify maximum clock frequency of

system. What happens if second output fed back to first input. Any changes?

What happens with timing if second output is fed back to logic between theflops?

129. What is difference between start imitation and start interlock for 3

phase motor protection ?

130. Why for transformer protection we protect transformer from 3rd

harmonics and 5th harmonics and what is the reason of generating these

harmonics in electrical system?

131. Whats the difference between Induction motor and servo motor

132. How to calculate the size of the conductor for particular load

133. Why heat produced at junction of two different conductor. What care

should

be taken to minimize it

134. How much %age of corona losses increases if frequency is increased to

25%.

135. What happen when ac power transmitted in unity power factor

136. What is the difference between the electrical and electronics

137. What is the meaning of TRI Vector meter?

138. What is IGBT?Where it is used? What is the difference between IGBT

and Thyristor?

139. When a square wave is applied to primary of a transformer then what

will be output wave form of secondary

140. What is bandpass of a transformer?

141. Resistance of a conductor in a close electrical ckt is practically zero

why?

142. Why C.T secondary are rated 5A generally


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143. Draw waveform of capacitor or inductor in a d.c ckt(during transient)

with zero resistance with it(in series or parallel)also neglect resistance of wire

144. What is the significance of per unit impedance ?

145. What is the function of commutator in dc motor?146. In case of delta/delta transformer if the one phase is blown out then

what will be secondary line voltage ?

147. What is linear motor?

148. What is the difference between ONLINE UPS and OFFLINE UPS?

149. Why electric shock due to dc is dangerous than that of ac?

150. Why the generating voltage in India is 11kv or why is it be transmitted

as multiples of 11?

151. How to calculate no. Of earthing pits and their diamensions? No. Of

lightning

152. arrester rods which are required to protect a building of 35 mtr?

153. What is difference between AC VVVF drive & Dc VVVF drive explain

their working principle?

154. Capacitor is load free component but why ampere meter shows current

when capacitor bank breaker is closed?

155. When birds sit on transmission lines or current wires doesn't get

shock?

156. What is the difference b/w winding insulation class and winding

temperature

class?

157. Is it possible for a feedback surge to travel over a wireless connection?

158. What is a DLC? Explain the advantage of DLC over PLC?

159. What are the tests to be taken on a transformer and generator?

160. Do you know how to measure the earth resistance? If so explain it

161. What is the make of breakers, transformers, generators? What are

their capacities and ratings?


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162. What are the starting currents of different motors and also what are

the running currents, and idle currents

163. Why a starter is used for a motor?

164.164. Do you know how to joint the H.T and L.T Cables?

165. How you take care of a motor from over loading and what are the

different overloading ratings of different motors?

166. Do you know the faults occurs generally in motors and how to rectify

them

167. Do you know the overhauling of a motor?

168. Do you know the alignment of a motor?

169. What accessories required to give the motor with given circuits and do

you know the ratings of those accessories

170. Do you know how to connect a motor of different H.Ps?

171. Do you know how to maintain a generator, if so what are

thosemaintenances?

172. How do you maintain the batteries for generators, what is the daily

maintenance of a generator?

173. How do you maintain the earthing resistance?

174. What should be the earthing resistance of an industrial substation and

also


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175. What should be the house hold earthing resistance?

176. What is the rating of your substation and what are the different types

of substations

177. What are the different protection systems used to protect the

transformer internally and externally?

178. What are the different ratings of the fuse units for different

distributions at your organization?

179. What are the different protection systems takes place on control panel

board?

180. What is meant by H.R.C fuse?

181. Do you know how to measure the earth resistance? If so explain it

182. What are the different sizes of cables for H.T and L.T side of supply?

183. Is your generator is automated or manual if so do you know the

circuits?

184. How do you connect the capacitors on polyphase circuits?

185. What is the power factor you maintain at ur organization?

186. What is the max demand on your transformer and your company


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187. What is the rating of your capacitor bank at your company.

ee question ram

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