ETO QUESTION BANK DC MOTOR 1. Name some parts of a D.C motor. 2. how many D.C motors are there? 3. Is D.C motor an Induction motor? 4. why a D.C motor take heavy inrush current? 5. how to reduce the starting current of a D.C motor? 6. on which factors does back e.m.f depend? 7. of following figure, how could you control the speed? 8. What is commutator? why it is used in D.C motor? 9. why in some A.C motor we also find commutator? 10. Why speed remains almost constant in a shunt motor? 11. why a series D.C motor never to be started without any load? 12. why a shunt D.C motor does not start with dangerously high speed? 13. what is a four point starter? what are the points? 14. what is WARD-LEONARD method? 15. what are the applications of D.C motors? 16. what is an universal motor? what are the main advantages of it? 17. what is stepper motor? 18. what are appliances used on-board ship with D.C motor? * kick motor * St. gear control * window wiper * siren speaker 19. what is differential compounding? 20. what is cumulative compounding? 21. how will you determine the force's direction in a D.C motor? AC MOTOR, Date:15/6/20 1. How many types of AC motor are there? 2. why an AC motor take heavy starting current? 3. why revolving magnetic field is necessary? 4. why single phase motor is not self starting? 5. explain capacitor start motor. 6.what are the disadvantages of split phase motor? 7. What is the speed-torque characteristics of an SCIM(squirrel cage induction motor)? 8. what is constant torque, constant H.P region? 9. what will happen if an induction motor run at synchronous speed? 10. what is the condition that an induction machine be run in generator mode or motor mode? 11. can an induction motor be made generator? how? 12. what are the starters used with SCIM? 13. what is MPCB? what protection we get from this device? 14. how would you measure the negative phase sequence intensity of a motor? 15. what is priming/purging in a centrifugal motor? 16. what is S.W.G? what is chassis winding? 17. why the core of a motor is sheeted? 18. why fan is used with motor? 19. what is soft starter? can i change speed of a motor with this device? 20. In a auto-transformer start motor how many contactors are used? 21. if you change any 2 phase of a 3 phase system, why the rotation get reversed? 22. what will happen to a motor during single earth fault in insulated system? 23. A motor is running, suddenly power gone, but before the motor speed become 0, again power came, is it a problem for motor? 24. what is single phasing? 25. can a 3 phase motor be run at 1 phase? 26. why commutation is seen sometime in some A.C motor? 27. What Is slip ring motor? draw block diagram of SCIM, slip ring, synchronous motor. 28. what is the advantage of Slip ring motor over SCIM? 29. how a synchronous motor be started? 30. how a synchronous motor be made to produce reactive power? 31. can a synchronous motor be run at asynchronous speed? 32. what will you find in a motor nameplate? 33. how a motor be started remotely and locally? 34 what will you do if a motor is submerged under salty water? 35. How to take megger readings of a motor? 36. what is series lamp test of a motor? 37. name some motor parts. 38. what is constant H/P, constant torque motor, what will be their configuration? 39, what will be the cable size/L setting, C.B setting of 15 K.W motor? 40. what are the maintenances of a motor? 41. For what reasons a motor be over loaded? 42. what will you find in a motor terminal box? 43. how motor speed be varied? 44. How does a V.F.D work? 45. If supply voltage becomes low what will happen to a motor? 46. if supply frequency is low what will happen to a motor? 47. what is pole changing method for 2:1 speed variation? 48. what is the common cause that make supply cable of a motor to be heated up ? 49. what is shaded pole motor? 50. when does a motor stall? Generator-L-C Load, Power Factor, Date: 16-6-2020 1. What is excitation of a generator? 2. What is brushless alternator? 3. What is pilot exciter? 4. What are the functions of A.V.R? 5. Why a generator is overloaded? 6. Why generator is rated in K.V.A? 7. How the reactive power demand of load is met? 8. What is compounding excitation? 9. what are the protection schemes for an alternator? 10. what is reverse power protection? 11. If generator is rated i.e. 100 KVA, what does it mean? 12. What are the limitations of a power system? 13. What is the process of voltage development in a generator? 14. what is self excitation and separate excitation? 15. If your generator is failed to build up voltage though A.V.R is fine, what will you do? 16. How to perform the Megger test of an alternator? 17. why generators starting current is high or what is starting instability? 18. how to change the frequency of a generator? 19. How an electronic governor work? what are inputs and outputs? 20. How fuel is delivered to inlet v/v? 21. what is preferential trip? which loads are preferred to get tripped? 22. what is power factor? for which load the power factor deteriorates? 23. What are constant R(Hot Plate), Constant I(hoist motor), Constant f(motor, fixed speed)load? 24. If voltage reduces to a Hot Plate in Galley, what will be the current phenomenon? 25. what will you do to improve your power factor? 26. Can reactive power locally supplied? 27. without inductor or capacitor how would you generate reactive power; electronically? 28. what happen to a motor when it's power factor is improved by a shunt capacitor? 29. what will happen to fuel when your electrical power factor improved? 30. If you find R-L-C series load, will you get more voltage across any R or Lor C load than supply voltage ? or in parallel load will you get more current through any branch than supply current? WHY? 31. How a generator is started? 32. what will happen if lube oil pressure is low? 33. how cable from generator is taken to electrical control room in a ship? Date:17/06/2020, Topics: Power System 1. what is fault current and overcurrent? 2. What is discrimination? 3. What factors determine the fault current? 4. what is short circuit calculation? what data do you need for this calculation? 5. what is load calculation? why does ship's load vary? 6. what is shunt trip and UVT trip? 7. how would you arrange relay switching and C.B trip? 8. which C.B will be used in a H.V system? why? 9. what is the oil made for C.B or transformer? 10. what is arc? 11. what is the difference between fuse and C.B? 12. how does a relay work? 13. what is symmetrical fault? 14. why D.C component must decay after fault? 15. what is A.C.B? how would you close the contact? 16. what is O.C.B? 17. what is MCB? DP MCB? TP MCB? 18. what is the protection scheme of a MSB? 19. what R.R.R.V? 20. Why does a C.B flashes? 21. what is S.T.C of a cable and breaker? 22. what is H.R.C fuse? 23. what cable will be used for V.F.D? 24. What is M.C.T? what is bulkhead penetration? 25. what is cable termination and cables gland? 26. what type of cable should be used for FDS system? 27. what is cable tray? 28. what us armour/shield/screen? 29. what types of cable should be used for bridge equipment? 30. what is XLPE ? 31. What is capacity of a 1x95 rm cable and 3x95 rm cable? 32. will current capacity of 35 rm cable be same for both 35* C and 55*C? 33. what are the limitations of cable capacity? 34. If insulation of cable shows low resistance, what will you do to bring back the insulation strength? 35. What is Polarisation Index? 36. why flex cable carry more current than stranded being of same dimension? 37. why a.c resistance is higher than d.c resistance? 38. what is sag? 39. what is bending radius of a cable? 40. how does thermal O/L relay work? ELECTRONICS, Date: 18/6/20 1. what is depletion region? Diffusion of carrier? 2. What is Rev. Bias and Fwd. Bias? 3. what is major carrier and minor carrier? 4. what is knee voltage, Peak inverse voltage? 5. what is ripple factor? 6. what is power diode? 7. What is the out put of half wave & full wave rectification? 8. compare among several types of rectification? 9. what is clipper? 10. what is thyristor? why we need it? 11. what is reverse blocking mode of SCR? 12. what is firing angle of SCR? 13. what is transistor? what is Common Base configuration? 14. If you need current amplification, which mode of transistor biasing will you prefer? 15. what is the construction of a transistor? 16. what is JFET? 17. what is pinch off voltage? 18. why saturation occurs at a certaint point of JFET characteristics? 19. How a FET is controlled? 20. What is MOSFET? what is DMOSFET? 21. what is substrate? 22. what is EMOSFET? 23. What is comparator? 24. what is an OP-AMP? what are the characteristics of it? 25. what is inverting and non inverting terminal? 26. what is a proportional controller? how would you achieve it by OP-AMP? 27. what is an integrator controller? how would you make it? 28. what does integrator mean in a controller? 29. what is a derivative controller? how would you make it? 30. what is PID controller? 31. what is cycloconverter? 32. what is synchro converter? 33. draw an inverter circuit. 34. why cyclo or synchro converter is needed in a vessel? 35. what is V.F.D, how would you control a motor by V.F.D? 36. what is a microcontroller? Name an I.C name of it? 37. what is input output port in a micro-controller? 38. what is alpha numeric display? 39. what is machine language and hex code? 40. what is the binary digit of decimal 349? 41. what is memory? how many types of memory are there? 42. what is peripheral? 43. what is ROM and RAM 44. what is transducer? what is sensor? what are the characteristics of a sensor? 45. what is 4-20 mA sensor? when should we prefer it? 46. what is 0-5 V sensor? 47. what is thermostat, thermistor, RTD,LDR? 48. what is tachometer? 49. draw a electrical block diagram or SLD of a GMDSS system for A4 area. 50. draw a SLD of auto pilot. 51. what is a double acting cylinder? is 3/2 way or 5/2 way v/v compatible with it? 52. what is limit switch? 53. what is a proximity switch or sensor? 54. what is the software name used for electro pneumatic and hydraulic simulation? 55. what is telemeter? MACHINERIES, Date:20/6/20 1. Name some decks of a ship. 2. what is bow thruster and stern thruster? 3. what is azimuthal thruster? 4. what is diesel electric propulsion system? 5. why boiler is used in ship? why heater is used in ship? 6. what is HVAC system? ans: Heat Ventilation Air Conditioning system 7. what is braking resistor? 8. what is HPU? why we need them? 9. what will you do if emergency occurs for steering gear system? 10. what is ringer? 11. what is engine order telegraph? 12. what is signal column? 13. how will you start a main engine? what is firing order? 14. what is auxiliary engine? 15. for fire fighting which equipment are found on board? what is sprinkler? Inergen system? 16. what is fire and safety plan? 17. what is heat detector? 18. what is manual call point and -----repeater? 19. what is console? 20. what is CPP and FPP? what is shaft generator? 21. what is cable tray, bend, riser? 22. what is MCT, frame,wedge,module? 23. what are the relays found inside MSB? 24. what is differential protection? when it is needed? 25. where to put emergency lights? 26. what is end of line resistor? what is addressable detector? 27. what type of cable is used with FDS,NAVG.,VFD and POWER? 28. what are alarms of engine? 29. what is oil mist detector? why we need it? 30. what is oily water separator system? why we need it? 31. what will you do if lube oil pressure shows low? 32. what is plate cooler and tube cooler? 33. what is ICCP and ICAF? 34. How does a echo sounder work? 35. what is sounding? why we need it? 36. what is A0, A1 zone? 37. what is IP 68? 38. draw an antenna arrangement of a ship. 39. what is CVS and window wiper? how to face the problem of ice accumulation on bridge windows? 40. what is TYFOON? what is MORSE CODE? 41. what are the angles of PORT,STBD and STERN light view? 42. How many MASTS are there is ship? 43. why two types of RADAR is needed? 44. what are GMDSS set? 45. What are found on bridge console? 46. what machineries are found inside engine room? 47. what are found on engine control room console? 48. what is a 4-stroke engine? 49. what type of motor is used for anchor winch? 50. what is shaft grounding? MISCELLANEOUS 1. what is ship voltage and frequency? 2. what is the duty of an Junior electrical officer in a ship? 3. what is shock voltage and current? 4. why should voltage of control system be kept low? 5. what is insulated system and what are the advantages? 6. what is non insulated system and what are the advantages? 7. what will you do to detect the earth fault? 8. what is double earth fault? 9. what is NER? what is the advantage of it? 10. what is insulation class? 11. when to take insulation readings of a motor? 12. what is polarisation index? 13. what is guard terminal? 14. what is a standard insulation value of any system? 15. can you measure R or continuity during live electrical system? 16. how would you check a diode? 17. why we need megger to check insulation rather than AVO meter? 18. How does a clamp on ammeter work? 19. how to measure DC current using clamp ammeter? 20. How does a RCB work? 21. How to find the location of any fault? 22. What is shore connection box, why we need it? 23. what are the equipment found inside shore box? 24. How would you check the phase sequence of any system? 25. Which factors determine the fault current level? 26. what is discrimination? 27. How would you bring back the insulation strength of a cable? 28. What is "marine type"? 29. What is leading and lagging system ? 30. what is VAR meter? 31. What are the purpose of AVR? 32. Why comparator is used in AVR circuit? 33. what is the typical out put and input value of a typical AVR for 440V system? 34. what is droop? 35. what are the parameters for making parallel operation system? 36. what will happen if voltage reduces of a generator in parallel operation? 37. what will happen if frequency reduces of a generator in parallel operation? 38. what is reverse power? what happens to an engine during reverse power? 39. why it is necessary to provide reverse power protection? 40. what is an induction generator? 41. what are the protections associated with a generator? 42. why generator cooling is necessary? 43. what is salient pole and cylindrical pole? 44. what is sub transient reactance, X"d%? 45. what is positive base and negative base diode? 46. what is compounding excitation? what are the advantages? 47. what is voltage sag? why does it happen? 48. what elements are found in parallel operation switchboard? 49. what is 2B 1D method? 50. what is a synchronoscope? why we need it? MISCELLANEOUS 1. what is U/V, O/V protection, what are the setting points of those relay? 2. What is U/F,O/F protection, what are the settings point of those relay? 3. What is the setting point of Earth fault, Leakage fault, Reverse power, Unbalanced current, Over load?----what is over current and fault current? 4. what is bus tie? 5. what are the typical sections in a MSB? 6. what are the maintenance of a generator? what is space heater ,why and where do we use it? 7. what are the maintenance of a transformer? what is %Z of a transformer? 8. what are the maintenance of a motor? 9. what is push switch, dip switch, toggle switch? 10. what is the most common case of induction motor failure? 11. how often a motor should be cleaned? 12. How many types of light are seen in a ship? 13. what is the luminous range of bridge room, engine room? 14. how does a incandescent lamp work? 15. how does a fluorescent lamp work? what is the function of capacitor? 16. what are the maintenance of lights? 17. what is navigational light control and alarm panel? 18. what are the alarms found in ship? 19. what is X-MASS lighting? 20. which society determines the lighting regulation of a ship? COLREG 21. what is SOLAS,OHSAS(occupational health safety and security),IEC? 22. describe the refrigeration system. 23. draw a refrigerator electric circuit? 24. draw a battery construction. 25. what is sulphation, gassing and corrosion? 26. draw a battery charger circuit. 27. what are the battery maintenances? 28. what is specific gravity? how would battery charge state be known by it? 29. what is UMS (unattendant machinery space)? what is DEAD man alarm? 30. what is MIMIC panel? SCADA system DIAGRAM LIST * insulated and non insulated system * lamp test * typical SLD of a ship * SLD of a emergency switchboard * Antenna arrangement * SLD of GMDSS, Autopilot * X-MASS lighting * clamp on ammeter, DC & AC * megger testing of a motor * Starter diagram: DOL/Rev,Fwd/Star Delta/auto transformer/Soft/DC 4 point * Ward Leonard * DC series/Shunt motor * brashless alternator * AVR diagram * megger meter electrical diagram * switchboard/generator/motor protection scheme * single earth fault schematic diagram * Cable construction * ACB and HRC fuse * Shore connection box * parallel operation box * switchboard section * HV ship SLD * Refrigeration system * governor (electronic) diagram * all electronics IC diagram taught to you * FDS simple loop diagram * steering gear diagram, Hydraulic * crane diagram, Hyd *charger circuit diagram. * Inverter diagram. ++++++++++++++++++++++++++++
