MD Helicopters 369-500, Maintenance Instructions Manual

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CSP-HMI-3
MD Helicopters, Inc
.
MAINTENANCE MANUAL
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96-10-00
Page 203
TR16-001
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.
NOTE:
The electrical system voltage level is to
be adjusted for a specific generator output
voltage, according to prevailing ambient
temperatures. (Ref. Table 201)
(1). Access power distribution center under
pilots seat structure.
NOTE:
Protective coating on component termi­
nals must be removed to ensure proper con­
tact between meter leads and component.
Make Sure Generator Control
Unit is set according to applica­
ble battery installed (Ref. Table 201). Fail­
ure to adjust Generator Control Unit to the
correct settings can damage battery.
(2). Connect a precision voltmeter (ST1009)
to E5 and terminal 1 of AS301 shunt
(Ref. Figure 202).
Avoid steady-state operations
(specified as a dwell time of
more than one second) between power tur­
bine N
2
speed avoid range (Ref. applicable
Pilot's Flight Manual for ranges). Failure of
the power turbine can occur.
(3). Start engine (Ref. applicable Pilot's
Flight Manual).
(4). Set GEN switch to ON and remove all
electrical system loads.
(a). Make sure all circuit breakers are
ON (pushed in) and all switches are
set to OFF/SAFE or NORMAL.
(5). Hold the collective pitch stick full down
and let the N
1
idle speed stabilize (Ref.
applicable Pilot's Flight Manual).
(6). Increase engine speed to 100% N
2
, with
No-Load condition, (Ref. step (4a).)
(7). Check voltmeter for the correct reading.
(a). If incorrect voltage indication is
shown, turn GCU voltage adjustment
screw slowly for incremental voltage
increase or decrease as necessary to
get the correct voltage setting.
(8). Set all electrical switches to ON to
provide a Full-Load condition of
electrical systems.
(9). Check and record voltage reading.
(a). The GCU must keep generator
output 0.5 Vdc.
(10). Restore helicopter electrical systems to
No-Load condition (Ref. Step (4).(a).)
(b). Keep a flat rotor pitch.
(c). Decrease engine speed to stabilize at
the appropriate N
1
idle speed range
(Ref. applicable Pilot's Flight Manu­
al).
(11). Set all electrical switches ON to repeat
Full-Load condition.
(a). Make sure that GCU is within limits
recorded in Step (9). +0.5 Vdc.
(12). Shut down engine.
(13). If voltage does not regulate to specified
limits, replace GCU and do steps (1).
thru (12). again.
(14). Disconnect and remove voltmeter.
CAUTION
CAUTION