S18
K15 3
X
A
S16
P4
S15
1
K15
R2
P14 B
1000
P4
2
LO.P
C2
C1
C3
S14
0.047uf
0.047uf
0.047uf
C
100V
100V
100V
P4
S9
P1
P3
P1
42 43
+
A
P1
P15 K
S9
F5 P16
P1
P1
15
14
Y
A
15A
BT1
P14
W P4
A
L F. W.
1 K16 3
K10
P16 B
S21
2
3
LOW FUEL LEVEL
BT2
1
14
16
15
LOW OIL PRESS
12
3
2
2
C4
HIGH COOLANT TEMP.
0.047uf
3
K11
100V
OVER/UNDER FREQ.
3 K12
8
FAULT
13
OVER/UNDER V
2
2
C5
9
INDICATOR
3K13
DC OVER V
0.047uf
10
100V
32
A1
2
RUN
6
11
C8
K14
5
0.047uf
7
4
17
GH J KL MN r
100V
P4
ENG
GEN
FAULT
FAULT
H J KLMNP j
TB3-2
K8
K9
P2
16 15 14 13
17
12
18
S22
S13
FAULT
FAULT
FAULT
DS 3 IND 3
11 LOCATOR
RESET
SWITCH
1
2
F6
15A P16
P2
G
F
P4
A
B
ASf07052
Figure 7-52.--Simplified schematic for fault locator switch.
depresses the accelerator pedal to vary the speed
positive than the cathode voltage. The SCR Q2 is then
reference signal to the electrohydraulic governor.
turned on. A path for current flow is created from the
Varying this reference signal causes the governor to
ground potential (terminal 17) through Q2 and CR14
change engine speed, which changes the generator
output. The vehicle's direction is controlled by a relay
path for current flow is also created through Q2 to CR4
circuit that reverses the polarity of the voltage
(fig. 7-51) and to terminal 6. The negative path
delivered to the traction motor. A speed-sensitive
provided here completes the circuit for the fault locator
switch prevents changing the direction of travel if
switch and fault indicator light. The fault light comes
speeds are greater than 3 miles per hour.
on, indicating that a fault has occurred. You can
identify the type of fault by turning the fault locator
NC-10C MOBILE ELECTRIC POWER
switch. The fault light will go out until the switch is
PLANT
turned to the OVER/UNDER VOLTAGE position.
Then the fault light comes on.
The NC-10C (fig. 7-54) is a diesel engine-driven
unit designed for shore station use. This unit supplies
Vehicle Propulsion and Control System
90 kVA at 0.8 PF, 115/200 volts, three-phase, 400-Hz
power for servicing, starting, and maintaining
A dc series traction motor converts the dc
helicopters and jet aircraft. A portion of the electrical
generator output into mechanical power to drive the
power generated is rectified to supply 28 volts dc at 750
vehicle (fig. 7-53). With the mode selector switch set to
amperes (1,000 amperes intermittent) for aircraft
the PROPULSION position, excitation to the dc
starting.
generator is kept constant at battery voltage level.
Variations of vehicle speed are obtained by varying the
The power plant is self-contained, requiring no
input voltage to the motor. The vehicle operator
external electrical or mechanical source of power. It
7-43
