MD Helicopters 369-500, Maintenance Instructions Manual

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CSP-HMI-3
MD Helicopters, Inc
.
MAINTENANCE MANUAL
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The information disclosed herein is proprietary to MD Helicopters, Inc.
Neither this document nor any part hereof may be reproduced or transferred to
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purpose except as specifically authorized in writing by MD Helicopters, Inc.
Copyright
©
1999 − 2016 by MD Helicopters, Inc.
power out light flashes. None of the
other warning and caution lights flash
when they are illuminated.
NOTE:
The caution and warning lights indicat­
ing system functions with N
1
/N
R
EPO warn­
ing equipment. N
1
/N
R
sensing equipment
senses both low engine (N
1
) and main rotor
(N
R
) speeds.
J. Caution and Warning Indicator Lights
Description (369D/E/FF − 500N)
The caution and warning lights consist of
separate and removable modular units
mounted across the top of the instrument
panel. Each light indicator assembly contains
places for four midget, flange base lamps.
Caution light circuits are completed to ground
through their respective fault sensors.
Warning light circuits are completed through
their fault sensors, the dimming unit and the
EPO warning control unit which provides a
pulsating source of 28 Vdc for light flashing.
The dimming unit provides the indicator
lamps test circuits and a switching regulator
for instrument panel and instrument lighting.
The caution and warning lights function as
follows:
(1). Engine Out Warning Light:
The engine out warning light flashes
when engine speed decreases to
approximately 55% N
1
rpm or less,
and/or when N
R
speed decreases to
approximately 98% N
2
rpm or less (Ref.
Engine Out Warning System).
(2). Main Rotor Transmission Oil Tempera­
ture Warning Light:
If main rotor transmission oil tempera­
ture rises to 121
°
C (250
°
F), a tempera­
ture-sensing switch actuates to
energize the main rotor transmission
oil temperature warning light.
NOTE:
Modifications to wiring of main rotor
transmission oil pressure and temperature
warning light circuits are described in this
section (Ref. Wiring Modification to Prevent
Utility Light and Main Rotor Transmission
Oil Pressure/Temperature Warning Lights
Deactivation).
(3). Main Rotor Transmission Oil Pressure
Warning Light:
In case of a reduction or loss of main
rotor transmission oil pressure, below
approximately 15 psi, a pressure-sens­
ing sender energizes the pressure
warning light circuit.
NOTE:
Modifications to wiring of main rotor
transmission oil pressure and temperature
warning light circuits are described in this
section. (Ref. Wiring Modification to Prevent
Utility Light and Main Rotor Transmission
Oil Pressure/Temperature Warning Lights
Deactivation.)
(4). Battery Temperature Caution and
Warning Lights:
The amber BAT TEMP 140
°
F caution
light illuminates at a battery tempera­
ture of 140
±
8
°
F. The red BAT TEMP
warning light illuminates at a battery
temperature of 160
±
8
°
F.
NOTE:
On 369E helicopter S/N 384 and subs,
and 369FF helicopter S/N 076 and subs,
relay K200 (battery high temp) removes the
battery from the bus line if 160
±
8
°
F is at­
tained.
(a). Slim-Line instrument panels only:
Battery temperature caution and
warning light indicators are mounted
in a light-switch-and-horn housing
on the side of the raised top center of
the instrument panel center fairing.
(b). T-Panels only:
Battery temperature caution and
warning light indicators are located
with the caution and warning lights
below the instrument panel hood.
(5). Engine Chip Detector Caution Light:
When sufficient loose ferrous metallic
matter is magnetically accumulated by
either one of two chip detectors in the
engine oil system, the engine chip
detector caution light illuminates.
(6). Main Rotor Transmission Chip Detector
Caution Light:
When either one of two chip detectors
in the main rotor transmission accumu­