8-6 BRUSH
The brushes must be smooth where they
contact the slip rings. If not, polish smooth
the brushes with sandpaper. A brush that is
not smooth produces arcs between the brush
and slip ring leading to possible damage.
Usable brush lengths are from 5 mm to 15
mm (0.2 ” to 0.6”).
A brush shorter than 5 mm must be replaced
because decreased contact pressure
between the brush and slip ring lowers gen-
erator efficiency and output voltage.
8-7 A.V.R
(AUTOMATIC VOLTAGE REGULATOR)
1) Features
This AVR operates to control the field current
in order to maintain the ouput voltage for the
AC current, which generated by the magnetic
flux by the field coil.
0
2) Distinguish the Good and Bad Parts
For making a simple Good (G) / No-Good
(NG) judgement, refer to the following table
showing continuity test criteria when mea-
sured between lead wires using a circuit
tester.
(O&Y0 0.2") \
t - BRUSH
Circuit tester (with measuring range of more than 1 M Q When measuring continuity, set the cir-
cuit tester to the range reading a high resistance (1 M Q).
* Checking table for analogue circuit tester.
Analogue circuit tester Apply black 0 needle of the circuit tester
Yellow Red White Light green
Brown/Yellow
Yellow 03 03 co 03
Apply red @ Red co 100kQ co 200kQ
needle of
the circuit White 33 50kR 03 100kQ
tester -Light green 16
kB
220kQ 125
kQ
14kQ
BrownlYellow xl 185kQ 100 k!2 co
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