entirely different electrical characteristics. New
brushes are shaped to fit and seldom need sanding to
seat properly. If some brush sparking occurs after
replacing the brushes, run the plantunderalightload
until the brushes wear to a good seat.
Collector rings acquire a glossy brown finish in
normal operation. Do not attempt to maintain a bright,
newly machined appearing surface. Ordinary clean-
ing with a dry, lint free cloth is usually.sufficient. Very
fine sandpaper (#400) may be used to remove slight
roughness. Use only light pressure on the sandpaper
while the unit is operating. Do not use emery or
carborundum paper or cloth. Clean out all carbon
dust from the generator.
MEASURE FROM TOP FACE OF
BRUSH BLOCK TO TOP OF BRUSH
DC
AC
NEW
5/8"
11/16"
•
% WEAR
13/16"
7/8"
REPLACE
1"
1 1/16"
5/8'
REPLACE WHEN WORN TO 5/8'
FIGURE 28. GENERATOR BRUSHES
FIGURE 27. MEASURING BRUSH WEAR
20