Westerbeke 6.5KW - Page 97

2-wire unit
3 and 4 wire unit
5 Volts AC (Hot lead to neutral)
2.5 volts AC (each hot lead to neutral
approximate)
Residual voltage checks O.K. You can assume the rotating armature
and brush rig are O.K. The generator problem lies in the rec-
tifier and/or field coils.
Residual voltage not present. Check brush rig and static capaci-
tors. Check rotating armature resistance values and continuity
check found elsewhere in this manual.
3. Test operation of generator by by-passing bridge rectifier. Apply
12 volts DC to field leads on bridge rectifier (+) to (+) and (-)
to (-). Run generator (no load). Measure voltage output at
generator leads. Generator output with 12 volts DC excitation to
the field coils should be 50 to 70 Volts AC. If 50 to 70 volts AC
is produced, this should indicate that the generator is O.K., and
that the bridge rectifier is defective.
4. If no voltage is produced, check the static capacitor(s) that it
is not shorted to ground. If found faulty, remove connection from
output terminal at brush rig and repeat step #3.
5. Flash Field Coils
Units may lose their
residual magnetism
from extended stor-
age, rough handling
during installation
or disassembly and
assembly for instal-
lation, etc., re-
quiring the field
coi Is to be exc i ted
with 6 to 12 volts
DC to restore the
magnetism to the
generator. This is
done in the follow-
ing manner:
S top the eng ine and
remove the generator
end bell cover. This
will expose the
cooling fan, brush
rig assembly and
rectifier. Check
internal wiring1
refer to figure.
The positive (+)
lead from the field
coils is connected
t----230v ------I~
Armature
91
AC
Internal Wiring Diagram
Basic 4 Wire
6-12 Volt
DC Battery