TM 5-6115-434-12
Section III. CONTROLS AND INSTRUMENTS
2-6. General
This section describes the various controls and instruments and provides the operator/crew sufficient information to
insure proper operation of the power unit.
2-7. Gas Turbine Engine Controls and Instruments
a.
General. The purpose of the engine controls and instruments and normal and maximum indications of the
instruments are described below. The engine controls and instruments are grouped in the lower left corner of the
instrument panel. (See fig. 2-14.)
b.
Battery Charging Ammeter (fig. 2-14).
(1)
Description. Dial pointer gage, calibrated to indicate -30 to +30 amperes in 1 ampere increments. Scale is
colored red from -30 to 0 and green from 0 to +30.
(2)
Purpose. To indicate the battery charging current during operation of power unit.
(3)
Indication. Battery charging current of about +11 amps after initial engine start, charging current of +2 to +
5 amps after a short period of power unit operation.
c.
Fuel Line Heater Circuit Breaker (fig. 2-14).
(1)
Description. A press-to-reset circuit breaker button installed in the fuel line heater circuit.
(2)
Purpose. Provide short circuit and overload protection for a fuel line heater circuit. The circuit breaker
opening amperage (15 amps) is marked on the reset button. (Used with winterized units only.)
d.
Fuel Line Heater Indicator Lamp (fig. 2-14).
(1)
Description. A filament type press-to-test lamp with a red lens.
(2)
Purpose. Illuminates to indicate that the fuel is sufficiently warm for engine starting. (Used with winterized
units only.)
e.
Fuel Heater Switch (fig. 2-14).
(1)
Description. A three position toggle switch.
(2)
Purpose. To energize a fuel line heater circuit. (Used with winterized units only.)
f.
Fuel Boost Pump Switch (fig. 2-14).
(1)
Description. A two position solenoid-held, on-off toggle switch.
(2)
Purpose. Energizes the fuel boost pump to deliver fuel to the engine fuel control unit at a constant
pressure (15 psig). Will trip to OFF position when master switch is in RUN or START position.
g.
Exhaust Gas Temperature Indicator (fig. 2-14).
(1)
Description. Dial pointer gage, calibrated to indicate
°
to 1800
°F in 100° increments to 900°F, 50°
increment from 900°F to 1500°F, and 100 increments from 1500°F to 1800°F. The scale is colored green from 0 °
to
1225F and red from 1225F to 1800°F.
(2)
Purpose. To indicate exhaust gas temperature in the engine exhaust pipe during operation.
(3)
Indication. Exhaust gas temperature shall not exceed 1260 °F during engine acceleration or 12250F during
steady-state operation at full load.
h.
Ready to Load Indicator Lamp (fig. 2-14).
(1)
Description. A filament type press-to-test lamp with a green lens.
(2)
Purpose. Illuminates to indicate that gas turbine engine has accelerated to approximately 95 percent of
governed speed and is ready for application of load.
i.
Emergency Operation Indicator Lamp (fig. 2-14).
(1)
Description. A filament type press-to-test lamp with a red lens.
(2)
Purpose. Illuminates to indicate that the emergency operation switch is on and that the power unit is
operating with protective devices bypassed.
j.
Emergency Operation Switch (fig. 2-14).
(1)
Description. A two position on-off toggle switch. A red lockout guard is installed over the switch to prevent
accidental actuation of the switch.
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