MD Helicopters 369-500, Maintenance Instructions Manual

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CSP-HMI-3
MD Helicopters, Inc
.
MAINTENANCE MANUAL
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[ Chapter 96 TOC ]
96-05-00
Page 201
Revision 8
The information disclosed herein is proprietary to MD Helicopters, Inc.
Neither this document nor any part hereof may be reproduced or transferred to
other documents or used or disclosed to others for manufacturing or any other
purpose except as specifically authorized in writing by MD Helicopters, Inc.
Copyright
©
1999 − 2016 by MD Helicopters, Inc.
BATTERY AND TEMPERATURE SENSING
MAINTENANCE PRACTICES
1. Description and Operation
(Ref. Figure 201) The battery is a recharge­
able, nominal 24 volt 13 ampere hour (amp
hr), 19 cell, nickel cadmium (ni-cad) battery
capable of starting the engine at temperatures
from -25
°
to +130
°
F (-22
°
to +55
°
C). (For
information on optional 17 amp hr, 20 cell
battery, refer to Section 96-05-10.) Nineteen
identical and individually replaceable battery
cells are contained in separate molded nylon
cases and interconnected by bus bars. Cells are
equipped with removable filler cap vent plugs.
Two battery temperature sensing switches
inside the battery sense any high battery
temperature and function with battery
temperature sensing equipment. The low
(140
°
F) temperature switch activates a
caution light and the high (160
°
F) tempera­
ture switch causes a warning light to illumi­
nate, at the temperatures shown. Only pure
distilled water is to be used for replenishment
purposes. Battery and cover are secured to
brackets on the pilot's compartment floor
structure. Gasses generated within the battery
are vented from cells out thru a ventilation
gap between each upper side edge of case and
cover.
2. Battery Handling and Servicing
Precautions
Electrolyte used in nickel-
cadmium batteries contains
potassium hydroxide, a caustic chemi­
cal agent. Serious burns result if elec­
trolyte contacts skin. Explosive gases
may be released from battery during
charging. Before removing battery
from helicopter, make sure that power
selector switch is at OFF position. Re­
moval or installation of battery con­
nector while battery is under load may
result in explosion, electrical arcing or
possible severe burns. When charging
battery, comply with procedures per
Battery Charging.
3. Battery Fault Isolation
For troubleshooting battery, refer to Section
96-00-00. Refer to Figure 203 for the battery
and temperature-sensing wiring diagram.
4. Battery Replacement
(Ref. Figure 201)
Consumable Materials
(Ref. Section 91 − 00 − 00)
Item Nomenclature
CM205 Dielectric compound
(1). Ensure all electrical power is off.
(2). Raise pilot's floor left access door.
Hand-press access door pivot pins from
hinge points and remove door.
(3). Disconnect battery connector.
(4). Remove attaching hardware and
battery from mounting flanges.
Place battery in protected area
away from any lead-acid type
battery.
(5). Lift battery and cover.
(6). Install serviced battery and secure
battery and cover to mounting brack­
ets.
(7). Apply generous coating of dielectric
compound (CM205) to male and female
connector pins and sockets. All surfaces
should be coated. Connect battery
connector; then wipe away excess
compound.
(8). Reinstall floor access door.
WARNING
CAUTION