MD Helicopters 369-500, Инструкция по техническому обслуживанию

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CSP-HMI-3
MD Helicopters, Inc
.
MAINTENANCE MANUAL
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96-10-00
Page 209
TR16-001
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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.
Copyright
©
1999 − 2016 by MD Helicopters, Inc.
5. Overvoltage Relay
(Ref. Figure 206)
NOTE:
Not used on 369E helicopters S/N 384 &
subs, 369FF helicopters S/N 076 & subs,
500N helicopters S/N 001 & subs and 600N
helicopters S/N 003 & subs, GCU replaces
functions of component.
The overvoltage relay (K103) protects the
electrical system from overvoltage. With
GEN-OFF switch at GEN, normally closed
contacts of overvoltage relay apply generator
output voltage to switch circuit SW
of reverse
current relay. When an overvoltage occurs in
range of 31.5 - 34.5 volts, overvoltage relay
energizes, removing power from switch circuit
of reverse current relay to remove generator
output from dc main power bus.
A. Overvoltage Relay Replacement
Consumable Materials
(Ref. Section 91 − 00 − 00)
Item Nomenclature
CM601 Insulation sleeving, electrical
CM815 Solder
(1). Ensure all electrical power is OFF.
(2). Gain access to overvoltage relay on
instrument panel structure. For
appropriate relay location, Refer to Sec.
95-00-00.
(3). Remove overvoltage relay.
(4). Unsolder electrical wiring from relay
terminal lugs.
(5). Ensure that insulation sleeving
(CM601) is used over wires and solder
(CM815) wires to terminal lugs of
replacement relay. Slide insulation
sleeving over relay solder terminals.
(6). Secure overvoltage relay on mounting
panels.
(7). Reinstall instrument panel fairing, if
removed.
6. Reverse Current Relay
(Ref. Figure 203) The reverse current relay
K300 (solid state) is mounted on the oleo
support fitting on the aft rib installation
between Sta. 124.00 and 137.50. The relay
isolates the generator from the dc main power
bus and battery to prevent current flow in
reverse direction when; the GEN-OFF switch
is OFF; an overvoltage condition exists; and
when battery voltage is greater than generator
output voltage.
NOTE:
D
Not used on 369E helicopters S/N 384 &
subs, 369FF helicopters S/N 076 & subs,
500N helicopters S/N 001 & subs and
600N helicopters S/N 003 & subs. GCU
replaces functions of component.
D
369D helicopters S/N 003 - 723 have re­
verse current relay mounted to oleo sup­
port fitting on right aft rib installation of
engine compartment.
D
369D helicopters S/N 724 and subs, 369E
helicopters S/N 001 thru 383 and 369FF
helicopters S/N 001 thru 075, the relay is
located on the left side of engine compart­
ment.
A. Reverse Current Relay Replacement
(Ref. Figure 203)
Consumable Materials
(Ref. Section 91 − 00 − 00)
Item Nomenclature
CM306 Lacquer, clear
(1). Ensure all electrical power is OFF.
(2). Disconnect and remove reverse current
relay.
(3). Ensure case electrical bonding surfaces
are clean on replacement reverse
current relay and on mounting surface
per Maintenance of Electrical Bonding
Connectors (Ref. Sec. 96-00-00). Secure
relay with attaching hardware.
(4). Connect electrical wiring to terminal
studs of reverse current relay.
(5). Apply coating of lacquer (CM306) to
all exposed electrical studs, terminals
and associated connecting hardware.