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POTENTIAL MOTOR DAMAGES & THEIR RECTIFIERS
Item
no.
Damage
Symptom
Damage
Cause
Rectifier
Remarks
1
The motor does
not work
or works
discontinuously
1.1. High wear & tear
of brushes or brushes
suspended in
brush-holders
Deinstall brush sets. If the length of a
brush is smaller than 8 mm, you should
replace the brush sets with new ones. In
case of suspending a brush in the brush-
holder, you need to loosen up the brush,
and possibly grind the side edges of
brushes with a fine-grained sand paper
(no. 600 or 800).
1.2. Wrong contact of the
brush with the commutator
due to dirt or shorting of the
commutator
Wipe the commutator with a brush
dampened with gasoline or alcohol. If
needed, grind the side edges of brushes
with a fine-grained sand paper (no. 600 or
800) or rectify any shortings.
1.3. Shortings or breaks
of rotor wiring.
Remove the motor, replace the rotor with a
new one.
2
Over-sparking of
brushes
2.1. Unground brushes
Grind brushes:
a) place the sand paper (600 or 800)
under the brush on the commutator, and
by rotating the commutator both ways
grind up the brushes.
b) by implementing the motor with a
110 V voltage (before the power system)
until the brushes are ground up (75%
of the contact surface)
2.2. Excessive wear & tear
of the commutator
If the raceway of the commutator has less
than 24 mm in diameter, the rotor needs
replacing.
2.3. Commutator
is dirty
Follow the instructions of para. 1.2.
2.4. Shortings or breaks
of the rotor
Follow the instructions of para 1.2. If no
improvement noticed, follow the
instructions of para. 1.3.
3
The motor
disrupts radio
waves.
3.2. Power supply system
damaged
Replace the power pack system
3.2. Over- sparking
Follow the instructions of para. 2.
4
Significantly
increased
rotational speed
apart from
over-sparking
4.1. Demagnetized
magnets
Replace the magnets.
5
Rotating pieces
grate against
each other
5.1. Damaged bearing
Replace the bearing with a new one.
5.2. Damaged
magnet spring
Replace the magnet spring.
5.3. Cracked magnet
Replace the magnet and the magnet
spring.
6
Transmission
works loudly
6.1. Work-worn
toothed wheel
Lubricate the wheel, and if it does not help,
replace it.
Attention:
The given damages and their rectifiers do not include all of the possible
cases.