300 Important DC Generator MCQ Question and Answer | PDF Free Download
1.The type of dc generator used for arc welding purpose is a
- ASeries generator
- BShunt generator
- CCumulatively compounded generator
- DDifferentially compounded generator
2.The essential condition for satisfactory parallel operation of two dc generators is that they should have same
- AkW output rating
- Bdrooping voltage characteristics
- Cpercentage regulation
- Dspeed of operation
3.The simplest way of shifting load from one shunt generator to the other operating in parallel is by
- AAdjustment of speeds
- BAdjustment of armature resistances
- CAdjustment of field rheostats
- DUsing equalizer connections
4.If field of one of two generators operating in parallel is made very weak, then it will
- ANot take any load
- BTake major share of load
- COperate as a motor and run in the same direction
- DOperate as a motor and run in the opposite direction
5.DC generators are connected to or disconnected from the busbar only under the foaling condition. This is done to avoid
- ABurning of switch contacts
- BSudden loading of the prime mover
- CMechanical jerk to the shaft
- DAll of the above
6.The main factor that leads to unstable parallel operationof flat or over compounded dc generator is
- ATheir rising voltage characteristics
- BUnequal series filed resistances
- CUnequal speed regulation of their prime movers
- DTheir drooping voltage characteristics
7.In the case of parallel operation of dc compounded wound generators for proper division of load from no load to full load it is essential that they should have the same
- AKW output rating
- BPercentage regulation
- CSeries field resistance
- DSpeed of operation
8.In parallel operation of two dc compounded generators provided with interpoles, the equalizing bar must be connected to
- AInterpole fields only
- BSeries fields only
- CUnction of series and interpole fields
- DNone of the above
9.DC machine armature Core Laminations are generally made of
- ACast iron
- BCarbon
- CSilicon steel
- DStainless steel
10.The thickness of laminations of a DC machine could be approximately
- A0.005 mm
- B0.05 mm
- C0.5 mm
- D5 mm
11.The commutator segments are connected to the armature conductors by
- ACopper lugs
- BResistance wires
- CInsulation pads
- DBrazing
12.In a commutator
- ACopper is harder than mica
- BMica and coper are equally hard
- CMica is harder than copper
- DNone of the above
13.In DC generators the pole shoes are fastened to the pole core by
- ARivets
- BCounter sunk screws
- CBrazing
- DWelding
14.According to Fleming’s right-hand rule for finding the direction of induced emf, when middle finger points in the direction of induced emf, Forefinger will point in the direction of
- AMotion of conductor
- BLines of Magnetic flux
- CEither of the above
- DNone of the above
15.Fleming’s right-hand rule regarding direction of induced EMF, co-relates
- AMagnetic flux, direction of current flow and resultant force
- BMagnetic flux, direction of motion of the conductor and the direction of EMF, induced
- CMagnetic field strength, induced voltage and current
- DMagnetic flux, direction of force and direction of motion of conductor