Piper PA-24 Comanche Service Manual page 548

PIPER COMANCHE SERVICE MANUAL
e. Cycle th. leaerator:
Method 1 - Move voltmeter 1.1Id. from "BAT" to "GEN" terminal
of
Kp1atot. Ret8rd
len~
erator sp"d until leMrater volta.e is redeed to 4 volts. lIove voltmeter leld back to "BAT"
terminal of recuJator. BriAI paerator back to specified spHd, . . note volt ..e Mttin•.
Method 2 - Comsect a v.iable resistance into the fi.1d circuit, a. ia Fiew.
~7.
Tum out
aU resistues. Operate ....rator at spKifiecl spHd. Slowly
mcr....
(tum
in) resistancs until
lenerator volt... is
reduced to 4 volts. TIU'Il aut aU rnistaae:e a.ain, aad note yolta.. settini
(with voltmeter cannec:ted as in Fiawe
~7).
R.plater cover _It be
in
pt.:e.
f. Note the thermometer relld.iac and s.lKt the HanDel R..... of Volta .. fer this temperature
as liated in specificatiOAl p.,apaph
9-41.
I. Note the volt_ter readinl with replater cover ia place.
h. To adjut voltace Mttin.
tum
adju'tina
SCNW
(Vi. . .
9-6).
Tum clockwise to increase
settine and counteNise to decreaae volta.. settiaa.
C,AUTIOH
If
"juatincscrew is tlUned down (clockwise) beyond NIlle, sprinC
support
may not return wbea SCrew is beckH off. In such ca., tum
screw caunterooelockwise until there il . .pI. clearance bet""ft
ICrew
held and sprinC support. Then bead spriDe suppcrt up care-
fully lIatil it touche. the screw
be_.
F ina! sattina of the uit
should al"ays be m_e by mcre..inl sprill. tension, ..ver by
Ie-
ducinC it.
If
settinc 11 too hiah adjust ait below required value
aDd then raise to exact ..Uina
by
mCNuinc the slKinl tension.
After each adjustIDesu and before takinl re.inl replace the NCU-
late.' coyer ad cyele the ..netatCll'.
Variable Reaistuce Method-
a. COIUlect ammeter and
~
ohm variable mistor
in
series with the battery as shown in Figure
9-8.
HOTE
It is
~
important that the variable resi.tance
be
cClllnected at the
"BAT" termmal u sftOW1l in FiC1U8
~7
rather thu at tbe "GEN"
terminal, even thouah the.e termiaaIa are in the .ame circuit. An
ezaminaUcm
oJ.
the wirine diaCram, Fipre
~3,
will sbow that
recu..
lation becins at the point where the sbuat windiccs are C:Clftftected
to the .rin circuit. Any smaU reliataace added to the c:ircuit be-
tween the lenerator ud this point
will
simply
be
oa.et by a rise in
ceneraar volt ... without affectinl the ClUtput shown
at
the ammeter.
b. Connect voltmeter between "BAT" terminal and cround.
c. Place tbelUlometerwithin ~, inch of reaulator cover to measure relulator ambient temperature.
d. Operate ceDer.or
It
specified speed. Adjust vlfiable resistor
lUlUI
current flow is
80010
amperes. If less current tbaft is required above is flowine it will be necessary to tum on aircraft
lights to pennit increased cenerator output. Variable resistance can then be used to decrease
ELECTRICAL SYSTEM
ISSUED: 8111172
3 82
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