TM 55-4920-328-13
following lens nomenclature:
Bleed Band Open (9)
De-ice Valve Open (10)
Fuel Filter Bypass (11)
T73 Fuel HTR Valve Open (12)
Bleed Band Closed (13)
De-ice Valve Closed (14)
T73 Fuel HTR Valve Closed (15)
The lens nomenclature on the switchlight units consists
of the following:
NII Phase Reverse (16)
Lamp Test (17)
NI Phase Reverse (18)
%NII (19)
EGT (20)
Fuel HTR Valve Open/Fuel HTR Valve Closed
(21)
NII Speed Control Pwr On (22)
T73 PWR Lever CW (23)
T73 PWR Lever CCW (24)
Auto Fuel/Emerg Fuel (25)
OSG Bleed Open/OSG Bleed Closed (26)
P1 Air (27)
Customer Bleed Air (28)
T73 Overspeed (28A)
Hot Air Open/Hot Air Closed (29)
Engine Fuel Solenoid (30)
Timer Start (35)
Timer Reset (36)
Three switches provided on operator's panel 3A3 are
placarded:
Start (31)
Ignition (32)
Preserve (33)
a.
Elapsed time indicator (timer) Ml. The elapsed
time indicator (37, figure 1-24), also referred to as the
timer, is a motor-operated digital stop clock operated by
117v ac, 60 Hz power. The timer is equipped with a
dc-operated clutch. The indicator dial provides a digital
readout from 000.0 to 999.9 seconds. Operation of the
timer is controlled by the TIMER START switchlight unit
(35). The switch is energized to start a timing operation.
When the switchlight unit is deenergized, the clutch
interrupts the timing cycle for instantaneous stoppage of
the timer during engine starting, and for coastdown after
fuel shutoff. Reset of the timer is accomplished by
energizing the TIMER RESET switchlight unit (36). The
maximum reset time is 2.0 seconds. The timer is
enclosed within a cylindrical housing with a mounting
flange conforming to AND 10401. Leading particulars of
the timer are contained in table 1-1.
b.
Throttle position indicator M2. The THROTTLE
POSITION indicator (8, figure 1-24) is an instrument
that provides display of relative positions of the engine
inlet guide vane actuator arm during a test. 26v ac, 400
Hz excitation power is input to the instrument at
connector pins A and B. Analog signals from a remote
IGV actuator arm position transmitter connected to the
data acquisition assembly are input to the indicator.
Needle movement to display inlet guide vane actuator
arm position is provided by a Magnesyn-type assembly
contained in the indicator case. Movement of the
indicator rotor is influenced by the strength of the
magnetic field induced within the associated stator
windings. The rotation of the needle and rotor shaft is
directly proportional to the input signal value from the
transmitter.
Change 5 1-45
