6 Flashcards
(85 cards)
1
Q
- A lead-acid battery is considered to be fully charged when the.
A)cells begin to gas freely.
B)SG and voltage remain constant for specified period.
C)SG reaches 1.180.
A
B
2
Q
- The preferred method of battery charging a Ni-Cad battery is constant.
A)voltage.
B)current.
C)power.
A
B
3
Q
- A fuse-type current limiter.
A)can be used as a radio suppressor.
B)limits current flow to a load.
C)opens a circuit after a time/current condition has been exceeded.
A
C
4
Q
- An external ground power supply can be used for.
A)all normal services required by flight and ground crew.
B)only the ground handling busbar services.
C)only the emergency busbar services.
A
A
5
Q
5 In unparalleled AC generation systems, the phase rotation of one generator in relation to the others.
A)must be synchronised prior to paralleling.
B)is unimportant.
C)must be BCA.
A
B
6
Q
6 . Sharing of electrical loads by paralleled DC generators is controlled by.
A)equalising circuits which control the field excitation of the generators.
B)automatic load shedding.
C)equalising circuits which control the speed of the generators.
A
A
7
Q
7 Excessive commutator sparking can be caused by.
A)rotating field diode failure.
B)brushes positioned on MNA.
C)weak spring tension.
A
C
8
Q
8 Before checking the SG of a battery recently removed from an aircraft.
A)take the temperature of the electrolyte.
B)carry out a capacity test.
C)allow to stabilise for one hour.
A
A
9
Q
9 Over-voltage protection circuits are activated.
A)before the over voltage limit is exceeded.
B)after a fixed time delay.
C)dependent on the magnitude of the overvoltage.
A
C
10
Q
- Which fault does not always trip the GCR?.
A)Under-frequency and under-volts.
B)Over-frequency and over-volts.
C)Over-frequency and under-frequency.
A
C
11
Q
- To flash a generator field the.
A)generator is on line and producing a voltage less than the flashing voltage.
B)generator rotates but is not on line.
C)generator must be stationary.
A
C
12
Q
- Voltage is controlled by.
A)the constant speed drive.
B)the voltage regulator.
C)the swashplate.
A
B
13
Q
- Distilled water should be added to a ni-cad battery.
A)only in the battery workshop.
B)at any time.
C)when fully charged.
A
A
14
Q
- Consumer loads are connected to a busbar.
A)in series so when loads are shed voltage is reduced.
B)in parallel so when loads are shed current is reduced.
C)in series so when loads are shed current is reduced.
A
B
15
Q
15 In an AC generation system, the frequency and phase rotation.
A)must be synchronised prior to paralleling.
B)is of no consequence after paralleling.
C)must be out of phase prior to paralleling.
A
A
16
Q
- Placing the battery master switch to off during flight will.
A)isolate the battery from the main busbar.
B)shut down the APU.
C)disconnect all power to the main busbar.
A
A
17
Q
- A voltage regulator installed in series with a generator field.
A)uses a voltage coil in series with generator output.
B)uses a voltage coil in parallel with generator output.
C)uses a current coil in parallel with generator output.
A
B
18
Q
- CSD warning lights on the flight deck normally indicate.
A)high oil pressure, low oil temperature low oil pressure, high oil temperature.
B)low oil pressure, low oil temperature.
C)low oil pressure, high oil temperature.
A
C
19
Q
- An AC generator used with a CSD.
A)needs a voltage controller to maintain voltage with increasing load.
B)does not need a voltage controller because current is kept constant.
C)does not need a voltage controller because voltage is kept constant.
A
A
20
Q
- High voltages on a generator in a parallel system should be prevented because.
A)it will trip the GCR.
B)it will damage the drive shaft.
C)it will cause high circulating current in the bus / other generators.
A
A
21
Q
- Over-voltage condition trips the generator. The time taken to trip the GCU depends on.
A)amplitude of voltage.
B)closing of fuel and hydraulic valves.
C)time delay circuit.
A
A
22
Q
22 When the temperature increases in a lead acid battery, the SG will.
A)decrease.
B)increase.
C)remain the same.
A
A
23
Q
23 Control of hydraulically powered emergency electrical generator frequency is.
A)by CSU.
B)by angle of swash plate.
C)by IDG.
A
B
24
Q
- Topping up a Ni-Cad battery in situ.
A)is not allowed.
B)is only allowed in the shop.
C)is permitted.
A
A
25
25. In a lead-acid battery after numerous checks, one cell has low reading.
A)It needs topping up.
B)It must be replaced.
C)It is defective.
B
26
26. An external power plug has two short pins. These are used for.
A)ground handling bus.
B)the interlock circuit.
C)a guide for correct alignment of the plug in the socket.
B
27
27 To confirm the state of charge of a ni-cad battery.
A) measure the discharge time.
B)subject the battery to load, check voltage and check the SG of each cell.
C)subject the battery to load and check the voltage.
A
28
28 Paralleling is used for.
A)AC and DC electrical generators.
B)DC electrical generators only.
C)AC electrical generators only.
A
29
29. If an aircraft has no battery charger, the battery is charged by.
A)constant current until a predetermined limit when it automatically switches to constant voltage.
B)constant current.
C)constant voltage.
C
30
30. The output of a carbon pile regulator with no variation of loading is.
A)stationary.
B)pulse width modulating.
C)fluctuating.
A
31
31. In a transistor voltage regulator, the voltage output is controlled by.
A)zeners and transistors.
B)diodes and transformers.
C)transformers and transistors.
A
32
32. When resetting the CSD on the ground, the engine should be.
A)rotating at Nsync.
B)rotating at idle.
C)stationary.
C
33
33. One of the main purposes of a CSD is to.
A)prevent engine overload.
B)enable generators to be paralleled.
C)maintain constant load on the generator.
B
34
34. If voltage and frequency of the generator drop to zero in flight, it would be an indication that the.
A)bus tie interlock is inoperative.
B)CSD driveshaft had sheared.
C)phase sequence detection circuit has operated.
B
35
35 Assuming all systems are operating normally, as aircraft electrical load increases, generator output voltage will.
A)increases and amperage output increases.
B)remain constant and amperage output increases.
C)decrease and amperage output increases.
B
36
36 When installing multiple batteries on aircraft, they are connected in.
A)series.
B)either parallel or series and switched between as an option.
C)parallel.
B
37
37 What is the small pin on the DC ground power connector?.
A)Positive to external power relay.
B)Positive to battery relay.
C)Ground or earth.
A
38
38 How is RAT driven?.
A)Airstream.
B)Compressor.
C)Fan.
A
39
39 How is an aircraft battery rated?.
A)Ampere hours.
B)Joules.
C)Watts.
A
40
40 The small pins in the power connector plug are.
A)negative.
B)neutral.
C)positive
C
41
41. Vibrating contact voltage regulator sensing coil is.
A)across the generator output.
B)in series with the field windings.
C)in parallel with the field windings.
C
42
42 . AC generator output indications are measured in.
A)KVA & KW.
B)KW & KVAR.
C)KW.
A
43
43. In the event of complete AC generator failure in an AC split bus-bar generation system, how is power maintained to the essential AC bus-bar?.
A)By power fed from a battery supplied static inverter.
B)By power fed from a hot battery bus-bar only.
C)By power fed from static inverter only.
A
44
44. In a paralleled AC generator system both A phases must be in synchronisation and.
A)CBA must equal ABC.
B)phase rotation does not matter.
C)CBA must equal CBA.
C
45
45. What controls output from the generator?.
A)BPCU.
B)GCU.
C)ELCU.
B
46
46. Specific Gravity in a lead acid battery should give an indication of.
A)charge.
B)electrolyte temperature.
C)electrolyte level.
A
47
47. What is the function of the generator control relay?.
A)Bring the generator on-line.
B)Connect the generator to the busbar.
C)Control output voltage.
A
48
48. In a split bus power distribution system.
A)each generator supplies its own bus and distribution system in normal operation.
B)generators are paralleled on connection to the tie bus.
C)power is split between 115V AC and 28V DC.
A
49
49. Flashing a generator field.
A)decreases resistance.
B)restores magnetism.
C)increases resistance.
B
50
50 An AC generator connected to a CSD requires.
A)a separate voltage regulator.
B)no voltage regulator as the CSD will control generator frequency.
C)no voltage regulator as the CSD will control the voltage.
A
51
51 On a C.S. driven generator, operation of the Disconnect Solenoid will disconnect the generator drive and.
A)it will automatically reset itself when the fault is rectified.
B)it can only be reset when all loads are switched off.
C)resetting can only be carried out on the ground.
C
52
52. A constant speed drive unit has a warning light indication.
A)for low speed.
B)for low oil pressure.
C)for when it is disconnected from the generator.
B
53
53. The purpose of an inverter is to convert.
A)DC to AC.
B)AC to DC.
C)AC to a higher frequency AC.
A
54
54 How can the state-of-charge of a nickel-cadmium battery be determined?.
A)By the level of the electrolyte.
B)By measuring the specific gravity of the electrolyte.
C)By measuring discharge.
C
55
55 Frequency (Hz) is the number of cycles per.
A)revolution.
B)second.
C)minute.
B
56
56. The three voltages of a three phase generator are.
A)90 degrees apart.
B)120 degrees apart.
C)180 degrees apart.
B
57
57. To restore the level of electrolyte which has been lost due to normal gassing during battery charging.
A)sulphuric acid must be added.
B)electrolyte of the same specific gravity as that contained in the battery must be added.
C)distilled water must be added.
C
58
58. A 12 volt lead-acid battery.
A)has 24 cells.
B)has 6 cells.
C)has 12 cells.
B
59
59. In a delta connected generator.
A)line volts equals 1.73 phase volts.
B)phase volts equals 1.73 line volts.
C)line volts equals phase volts.
C
60
60 When checking the specific gravity of the electrolyte in a battery.
A)one cell only need be checked as the remainder will read the same.
B)each cell should be checked as the readings may differ.
C)only the end cells need be checked as they contain the terminals.
B
61
61 Which aircraft circuit would be most likely to use frequency wild 200V AC?.
A)Hydraulic pump.
B)Standby compass.
C)Windscreen heating.
C
62
62 The output of a DC generator is controlled by varying the.
A)armature current.
B)engine speed.
C)field current.
C
63
63. A battery which is assumed to be 100% efficient and to have a capacity of 60 ampere-hours at the 10 hour rate will deliver.
A)6 amps for 10 hours.
B)60 amps for 10 hours or 6 amps for 10 hours depending upon the rate of demand.
C)60 amps for 10 hours.
A
64
64. Two 12V 25 ampere batteries connected in series will produce.
A)12V with 25 ampere hour capacity.
B)24V with 25 ampere hour capacity.
C)12V with 50 ampere hour capacity.
B
65
65. For battery charging, the electrical supply connected to the battery must be.
A)AC at 50 c.p.s.
B)AC at 400 c.p.s.
C)DC.
C
66
66 When using A.C. power on the bus bar you require 28V D.C. for battery charging.
A)an A.C. inverter would be required.
B)an A.C. transformer and rectifier would be required.
C)a D.C. transformer and rectifier would be required.
B
67
67. Two similar 12V batteries connected in parallel will produce.
A)24V e.m.f. with the same capacity as each battery.
B)12V e.m.f. with twice the capacity of each battery.
C)24V e.m.f. with twice the capacity of each battery.
B
68
68. If a nickel cadmium aircraft battery is not required for immediate service, it should be stored.
A)in the fully discharged condition.
B)in a totally dry condition.
C)in the fully charged condition.
A
69
69 Battery SG is measured using a.
A)hygrometer.
B)hypsometer.
C)hydrometer.
C
70
70. The frequency of an AC generator is dependant on the.
A)number of pairs of poles and the speed of the rotor.
B)number of conductors and the field strength.
C)field strength and the speed of the generator.
A
71
71 Single phase components in a 3 phase system may be connected between.
A)phases A and B only.
B)the phase and earth only.
C)any phase and earth or between any two phases.
C
72
72. A frequency wild supply would be suitable for.
A)instruments and navigation systems.
B)deicing loads.
C)3-phase torque motors.
B
73
73. Three 12V, 40Ah accumulators in series would give.
A)36V 120Ah.
B)12V 120Ah.
C)36V 40Ah.
C
74
74. Three 12V, 40Ah accumulators in parallel would give.
A)12V 40Ah.
B)12V 120Ah.
C)36V 120Ah.
B
75
75. An inverter can be an AC generator driven by.
A)an AC motor.
B)either an AC or DC motor.
C)a DC motor.
C
76
76. When mixing electrolyte for lead acid batteries.
A)the method of mixing is unimportant.
B)add acid to water.
C)add water to acid.
B
77
77 The RPM of a 6 pole, 400 Hz alternator is.
A)6000.
B)8000.
C)4000.
B
78
78. The ratio between apparent power and true power is the.
A)efficiency.
B)power factor.
C)power rating.
B
79
79 When operating two AC generators unparalleled, the phase of each.
A)is unimportant.
B)must be in opposition to one another.
C)must be synchronized.
A
80
80. An I.D.G (integrated drive generator).
A)does not require a CSDU.
B)incorporates the alternator and CSD as one unit.
C)has separate CSDU.
B
81
81. A P.M.G (Permanent Magnet Generator) is a small built in generator which.
A)only rotates after starting.
B)only rotates during starting.
C)provides initial excitation.
C
82
82. To parallel an alternator with another alternator the alternators must have the same.
A)frequency, voltage and phase relationship.
B)frequency, RPM and speed.
C)frequency, RPM and phase relationship.
A
83
83 Speed of an alternator may be controlled by.
A)keeping engine rpm constant.
B)varying the field current.
C)CSDU (constant speed drive unit).
C
84
84. Frequency wild' alternators supply.
A)capacitive circuits.
B)inductive circuits.
C)resistive circuits.
C
85
85 How is initial voltage build-up ensured in a brushless generating system, before full output is available from the voltage regulator?.
A)Excitation form the DC busbars is automatically provided during the start sequence.
B)A switch must be operated by the crew to provide excitation form the dc busbar to bring generator on line.
C)Permanent magnets are mounted between the exciter field poles.
C
