Taylor-Dunn SS-025-34 Operation, Maintenance, And Replacement Parts Manual page 124

Curtis PMC Troubleshooting
Check continuity from 'S1' to the frame of the
motor.
If you do not know how to test for continuity,
refer test to a qualified technician.
This should be an open circuit. If there is
continuity from 'S1' to the frame of the
motor, then the motor field is shorted.
Stop trouble shooting here and repair the
problem. When the repair is completed,
completely retest the vehicle before
lowering the drive wheels to the ground,
otherwise continue to Motor Inspection.
Motor Inspection
1. Remove and disassemble the motor.
2. Visually inspect the inside of the brush end housing. If there are any silver specs of metal
around the inside of the housing, it indicates that the armature has overheated and melted
the solder around the commutator. The armature is bad and the motor must be replaced.
Stop here and repair the problem, otherwise continue with the next test.
3. Visually inspect the armature wires where they loop around at the shaft end of the armature.
The insulation should be a light to medium reddish brown color. If the insulation is dark brown
to black or the insulation is cracked and peeling, then the armature has been overheated and
burnt. The motor must be replaced. Stop here and repair the problem, otherwise continue
with the next test.
4. Perform a continuity test around the armature commutator. Place one of the test leads on
a single commutator segment. While holding the first test lead on the segment, check the
continuity to the other segments around the commutator.
If you do not know how to test for continuity,
refer test to a qualified technician.
•
There should be continuity on each
commutator segment. If an open segment
is found, the armature is bad and the
motor must be replaced. Stop trouble
shooting here and repair the problem.
When the repair is completed, completely
retest the vehicle before lowering the
drive wheels to the ground.
Stop, do not continue. If you reached this point without a solution, then you may have an
unanticipated problem or have made an error during testing. It is important to review the
trouble shooting steps that have led to this point. The tests may need to be repeated.
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STOP