1
3
2
ASf07053
1. Dc drive motor
2. Differential and gear drive
3. Rear axle
Figure 7-53.--NC-8A self -propulsion package.
and underfrequency relays, thermal overload relays,
and fuses.
Power generation, both dc and ac, is controlled by
the operator from the control panel located at the left
front of the unit. The control panel contains four
functional groups of instruments--the electrical
receptacles and adjustable resistors, the ac controls,
the dc controls, and the engine controls.
ASf07054
DC Power System
Figure 7-54.--NC-10C mobile electric power plant.
The dc power supply of the NC-10C is obtained
operates efficiently at altitudes ranging from sea level
from a six-phase, full-wave transformer-rectifier, by
to 8,000 feet.
using three-phase, 400-Hz, 115/200-volt generator
The power plant is enclosed in a steel housing. The
output as a power source. The dc output voltage is
housing is fabricated in two sections, which are easily
regulated by a two-stage magnetic amplifier circuit.
removed to service the unit. Operating components are
The output dc voltage range is 22 to 39 volts. The
mounted on a four-wheel trailer, which is equipped
voltage is regulated within 0.5 volt at no load up to
with mechanical internal expanding wheel brakes. The
full load (750 amperes). The maximum output is 28
brakes may be set by a hand lever.
Vdc at 750 amperes continuous duty, or 1,000 amperes
intermittent (15 second on and 45 second off) for 8
Double-hinged doors provide access to the control
consecutive cycles applied to the dc cable).
panel, starting components, and three output power
cables.
Protective relays protect the power supply from
current and voltage overloads. A cable is provided for
The plant's electrical system is protected from
connection of dc power to aircraft. A cable reel is
overload by output circuit contactors, circuit breakers,
provided for cable stowage.
overvoltage and undervoltage relays, overfrequency
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