問題一覧
1
Line voltage with a delta type connection will be the same as
phase voltage.
2
On an aircraft DC generator the pole pieces are :
electromagnets
3
Armature reaction is when:
field excited, armature excited.
4
The AC waveform has mark-to-space ratio 0.5 this means :
the space is twice the mark
5
Three phase
star connection(Y)
6
Root mean square:
is the equivalent DC heating effect
7
Split phase means:
single phase
8
the most common type used at the A/C
is Shunt wound
9
Alternating polarity from an alternator takes on a distinct shape, known
as a sine wave.
10
Additional generator poles in a DC motors are provided
to Compensation for the armature reaction
11
The speed of a series motor is dependent
upon the load.
12
The peak value of an aircraft 115v single phase is :
162.6
13
A sine wave of RMS value 7.06 volts has a peak to peak value of.
20 volt
14
The max. Value of voltage in either (+ve) or (– ve) direction is.
The peak value
15
In the series motor, the field windings, consisting of a relatively :
few turns of heavy wire
16
If a DC shunt motor lost its residual magnetism it would :
run normally
17
The coil ends connected to adjacent commutator segment :
Lap winding
18
The Form Factor of an AC waveform can be found by.
RMS value divided by the average value
19
constant direction :
direct current
20
Square-shaped waveforms always have crest and form factors equal to 1, since
the peak is the same as the RMS and average values
21
Peak value=
RMS/0.707
22
The form factor of an AC waveform can be found by :
RMS value divided by the average value
23
If the heavy mechanical load is removed from a series motor the speed will:
increased and the armature current will decrease.
24
To decrease the arcing at the brushes in a high output generators we
add interpoles and compensating winding
25
Number of cycle completed per second :
frequency
26
The current consumed is decreased as the
rotation speed increased while starting in the DC motor.