Yale MPB040-E, Manual

Page: 104 / 130

Table 2. Commutator Problems
Problem Possible Cause Illustration
Heavy streaks and fine
grooves indicate the be-
ginning of damage to the
commutator. • Operation of the
motor in dirty and
abrasive condi-
tions.
• Continuous opera-
tion of a motor with
a light load.
• Brush pressure is
too low.
• Worn brushes.
Grooves and lines that
have followed the heavy
streaks and fine grooves
shown above. The arma-
ture must be removed
from the motor so the
commutator can be re-
paired. A commutator
with this condition will
cause the brushes to
wear rapidly. • Operation of the
motor in dirty and
abrasive condi-
tions.
• Continuous opera-
tion of a motor with
a light load.
• Brush pressure is
too low.
• Worn brushes.
Brush and Commutator Inspection 0620 YRM 0294
6