Section 5. Troubleshooting Model 8210/8250 Maintenance Manual
DC Electric Motors
5-10 Publication: 1146945/001, Revised: 25 Sep 2018
Unsatisfactory
Condition-Example of
Incorrect Commutator
Machining
Bars are low on entry and leaving edges causing
the brushes to ride on the middle of the bars.
Continued use may result in failure and damage
to other systems. The motor should be replaced
or recut at a qualified repair facility. Consider
more frequent scheduled maintenance intervals.
Brushwear07.tif
Unsatisfactory
Condition-Example of
Incorrect Commutator
Machining
Bars are low in the middle causing the brushes to
ride on the entry and leaving bar edges.
Continued use may result in failure and damage
to other systems. The motor should be replaced
or recut at a qualified repair facility. Consider
more frequent scheduled maintenance intervals.
Brushwear08.tif
Unsatisfactory
Condition-Streaky Film
With Commutator Wear
This is a further development of the third
example. Earlier corrective action should have
been taken. Continued use may result in failure
and damage to other systems. The motor should
be replaced or recut at a qualified repair facility.
Consider more frequent scheduled maintenance
intervals.
Brushwear09.tif
Unsatisfactory
Condition-Double Pole
Pitch
Darkening of commutator in sequences two pole
pitches apart. This condition may result from an
armature fault or some other fault. Continued
use may result in failure and damage to other
systems. The motor should be replaced or recut
at a qualified repair facility.
Brushwear10.tif
Unsatisfactory
Condition-Brush Contact
Mark
This condition may result from storage of the
machine for long periods with brushes in
position. It may also result from operation in
prolonged stall conditions. Storage marks are
easily removed with a polishing stone, see
“Polishing the Commutator” on page 7-85. Stall
marks should be cleaned and inspected for
damage or shorts. The motor should be replaced
if damage has occurred.
Brushwear11.tif
Unsatisfactory
Condition-Bar Edge
Burning-Cause High Mica
This condition is caused by high mica in every
slot and can be caused by incorrect or excessive
stoning. The same effect can occur on one bar
only. Chattering or loud operation may also be
noticed. Continued operation will result in
increased brush wear and may result in
commutator damage. The motor should be
replaced or recut at a qualified repair facility.
Brushwear12.tif
Condition Probable Cause Commutator Surface
Property of American Airlines
To Next Page
Loading...