MD Helicopters 369-500, Maintenance Instructions Manual

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CSP-HMI-3
MD Helicopters, Inc
.
MAINTENANCE MANUAL
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Revision 11
96-00-00
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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.
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1999 − 2016 by MD Helicopters, Inc.
(b). Heat pre-tinned cup or pin.
(c). Install wire or cable.
(d). Allow solder to solidify.
A. External Power Receptacle Replacement
(Ref. Figure 201)
Ensure all electrical power is
OFF during replacement of
power receptacle.
NOTE:
It may be necessary to disconnect
ground cable to external power unit relay
(helicopters 724 & subs.) for sufficient slack
to remove receptacle. If so, open right access
door of pilot's compartment floor for access
to ground cable.
(1). Disconnect, remove, replace and
reconnect defective receptacle assembly.
NOTE:
Aft terminal is negative (-) or ground;
center terminal is positive (+); and forward
small polarity pin is not used.
(2). Reconnect any cabling disconnected to
obtain slack for receptacle removal.
(3). Check for correct output voltage and
polarity at utility receptacle.
B. Replacement of Terminal Blocks and
Terminal Block Contact Tips
(Ref. Figure 203) Replace terminal blocks
and/or their contact tips, as necessary, in
accordance with FAA AC 43.13-1A and
aircraft standard electrical repair and replace­
ment practices and procedures. Also, when
necessary, refer to applicable manufacturer's
maintenance data (Ref. Table 201, Sec.
01-00-00) and special tools (ST1004). For
schematic and wiring diagram information,
refer to appropriate Section.
Ensure all electrical power is
OFF during replacement of ter­
minal blocks or terminal block contact tips.
6. Maintenance of Electrical Bonding
Connections
Consumable Materials
(Ref. Section 91 − 00 − 00)
Item Nomenclature
CM206 Chemical coating
CM234 Solvent, dry-cleaning
CM306 Lacquer, clear
CM801 Abrasive paper, silicon carbide
Ensure all electrical power is
OFF.
(1). When replacing bonding jumpers, use
dry- cleaning solvent (CM234) to
remove grease, oil or other nonconduc­
tive film from mating surfaces.
(2). When removing non-soluble films from
bonding areas, use grade 400 abrasive
paper (CM801) to lightly sand and
polish surfaces using care to remove
only a minimum of base material.
(3). After polishing aluminum alloys, apply
brush coating of Iridite No. 14-2 (Class
3) chemical film protection (CM206) to
mating surfaces.
(4). When removed bonding jumpers are
reconnected, ensure clear lacquer
finish, originally applied to cleaned
mating surfaces, will not act as an
insulator between mating surfaces.
Clean mating surfaces as necessary,
according to steps (1)., (2). and (3).
above.
(5). After connecting bonding jumper, apply
clear lacquer (CM306) to exposed area
of cleaned surface.
7. Electrical Wiring and Harnesses
(Ref. Table 202) Components of the power
supply and distribution equipment, and other
functional components and equipment of the
electrical system are interconnected by wiring
harnesses and are shown in Figure 205. Wires
in harnesses are terminated with electrical
connectors (plugs and receptacles), knife
splices, snap-in contacts, terminal lugs or
similar wire-end termination devices. Wiring
harnesses in the helicopter are secured and
protected by insulated straps and grommets.
CAUTION
CAUTION
CAUTION