TM 55-4920-328-13
Figure 1-7 Electric Start System Schematic Diagram.
the battery power contactors to route battery power to
the engine starter contained in the engine accessories.
Excessive engine starting will require switching to the
spare battery. Except for unusual duty requirements. it
is recommended that battery usage be alternated at the
regular calibration intervals. Control power for the
charger is provided through the INST POWER circuit
breaker CB8 17, figure 2-9) and the actuation of the
instrument power relay K1. To provide trickle charging
capability, the circuit breaker on-off switch (3, figure 1-6)
must be placed in the on position.
(5) Hydraulic start system.
NOTE
U.S. Army (USATSARCOM) authorized
ECP No. MEG-01, dated March 26,
1981, identifies the replacing of the
gasoline
engine
driven
hydraulic
starting unit and the battery starting
system with a Christie Rectifier Power
Supply
starting
system.
(Army
supported electrically driven units are
currently available.)
(a) The hydraulic start system (figure 1-8)
provides fluid starting power for gas turbine engines
equipped with hydraulic starters. The hydraulic start
system is located on the right side of the test trailer
assembly (figure 1-2), forward of the control cab
module. The system (shown schematically in figure 1-9)
consists essentially of a high-pressure pump assembly
driven by a gasoline engine, a tank assembly, 2
pressure gages (11 and 12, figure 1-8), a 10-micron
filter (5), a back pressure regulator, and 2 relief valves
(23 and 24). A solenoid-operated valve (10) is used in
the vent line of the main relief valve to select operating
pressures. Inlet, outlet, and case drain lines are used to
interconnect the start system to the hydraulic starter on
the gas turbine engine under test. Specification MIL-H-
83282A hydraulic fluid is the medium used in the
system. Quick-disconnect fittings are provided in the
supply and return lines for ease of connection to the
engine under test. The engine is an air-cooled
reciprocating unit rated at 65 horsepower at 2,800 rpm,
and is powered by a 90-octane gasoline. Starting power
for the gasoline engine is provided by a 12-volt battery.
The tank assembly is provided with a strainer to prevent
foreign
solids
from
entering
1-10 Change 4
