Precautions When Testing Or Servicing The Electrical System; Slip Ring End Bearing Assembly View; Testing Alternator Diagram - Piper Navajo Chieftain PA-31-350 Service Manual

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370
SEAL-INSTALL
SEAL
WITH LIP
carbon
TOWARD BEARING
INNER RACE
GREASE-
/
CAVITY
SPACER
TEST
voltmeter
BEARING
Figure 1 1-14. Slip Ring End
Figure 11-15. Testing Alternator
Bearing Assembly
11-15. TESTING OF ALTERNATOR.
a.
Wiring connections for bench testing the alternator are shown in Figure 11-15. Refer to the
individual specification pages for output test figures. Adjust the carbon pile, if necessary, to obtain the
specified voltage.
a.
Wiring connections for bench testing the alternator are shown in Figure 11-15. Refer to the
Alternator Service Test Specification paragraph for output test figures. Adjust the carbon pile, if necessary.
to obtain the specified voltage.
NOTE
Always refer to the electrical schematic (refer to Table XI-I) when
installing the alternator or testing the alternator.
11-16. PRECAUTIONS. The following precautions are to be observed when testing or servicing the
electrical system.
a.
Disconnect the battery before connecting or disconnecting test instruments (except voltmeter) or
before removing or replacing any unit or wiring. Accidental grounding or shorting at the regulator,
alternator, ammeter or accessories, will cause severe damage to the units and/or wiring.
b.
The alternator must not be operated on open circuit with the rotor winding energized.
c.
Do not attempt to polarize the alternator! No polarization is required. Any attempt to do so will
result in damage to the alternator, regulator or circuits.
d.
Grounding of the alternator output terminal may damage the alternator and/or circuit and
components.
e.
Reversed battery connections will damage the rectifiers, wiring or other components of the
charging system. Battery polarity should be checked with a voltmeter before connecting the battery. Most
aircraft are negative ground.
f.
If a booster battery or fast charger is used, its polarity must be connected correctly to prevent
damage to the electrical system components.
Revised: 10/15/82
ELECTRICAL SYSTEM
NAVAJO CHIEFTAIN SERVICE MANUAL
3D2