BATTERY
CHARGING
SYSTEM
BATTERY CHARGING, FLYWHEEL
ALTERNATORS
The flywheel alternator
is a
permanent magnet alter-
natorand uses asolid-state voltage regulator-rectifier
for controlling output.
Two different alternator systems
are
used with
NHC
and NHCV engines. One
is
a 20 amp Synch ro system,;
the other
is a 15
amp Phelon system.
A 30-ampere fuse
is
included
in the
battery charging
system
to
protect
the
alternator
in
case
the
battery
cables
are
accidently reversed. Replace the fuse with
Onan Fuse 321-0162, Buss AGC30
or
equivalent.
Weak ignition spark
or
a discharged battery indicate
trouble
in
the charging system. But before testing
the
engine's charging system, always check
the
battery
for serviceability.
TESTING
OR
SERVICING
Keep these points
in
mind when testing
or
servicing
the flywheel alternator:
1.
Be
sure output control plug (connector)
is in-
serted properly. Plug must bottom
in
receptacle-
eliminates
any
resistance
due to a
poor connec-
•
tion.
Keep clean'and tight.
•
2.
Make sure alternator stator leads are not shorted
together.
3.
Be
sure regulator-rectifier output control
has a
good ground connection. Mating surface
for
mounting must
be
clean and fasteners tightened
properly.
4.
Never reverse
the
battery leads.
Charging system tests require a fully charged battery.
20 AMP SYNCHRO SYSTEM
The
20 amp
flywheel alternator systems
use a
separate regulator and a separate rectifier, Figure 28.
Testing:
For
testing this system,
use a
voltmeter-
ohmmeter such
as
a Simpson"27.0. Various alternator
problems with individual test procedures are listed
in
table
2.
/
No Output—Stator Assembly: Examine leadwires
for
loose
or
broken connections
at the
regulator
and
rectifier.
Use the Rxl
scale
on the
ohmmeter
for
detecting opens
in the
stator. Disconnect-.the three
wires that come from alternator stator (two black, one
red).
Connect ohmmeter test leads
to red
leadwire
and ground
to
check continuity.
The
ohmmeter
reading should
be
about
2.0
ohms. See Figure 29
for
wiring diagram.
•
Next, connect meter
to
black leadwires and ground.
Approximately
0.1 ohm
should
be
read from either
black lead
to
ground.
If
no connection exists between
ground
and
black leads, stator assembly should
be
replaced.
RECTIFIER
STATOR ASSY.
SCREEN BOLT
TIMING HOLE
THROUGH
FLYWHEEL
FLYWHEEL
ON
PRESSURE COOLE
ENGINE
ALTERNATOR ROTOR
(PART
OF
FLYWHEEL ASSY.)
FIGURE 28. 20 AMP SYSTEM
21
To Next Page
Loading...
