PASCO SE-8657 MOTOR ACCESSORY - Manual (Page 30)

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Motor Accessory 012-06247A
¨
400
400
U-shaped base
400-turn coil
➤ Check to be sure the brush assembly is seated as far down on the shaft as it will
go.
➂
Orient the brush holder perpendicular to the base of the Coils and Cores apparatus. Place
the two 400-turn coils from the Coils and Cores Set onto the poles of the core.
➃
Gently lower the armature onto the shaft. The split ring commutator should be down.
Carefully rotate the armature back and forth to separate the brushes and allow the commuta-
tor to slip down between them. If necessary, insert a pencil or similar object between the
brushes to separate them. Use only the most delicate force to avoid bending the brushes and
necessitating adjustment or repairs.
Procedure
➀ Connect the motor the power source as shown in Figure 2. All connections may be made by
inserting banana plugs into the openings in the ends of the plastic brush holder and the
external coil forms. Do not turn on the power source yet.
➁
Rotate the armature and observe how the segments of the split ring commutator contact
different brushes as the armature turns.
➂
Remove the armature from the shaft by grasping it between your thumb and forefinger and
rotating it back and forth while lifting gently. If necessary, insert a pencil between the
brushes to gently separate them so they don’t prevent removal of the armature.
➃ Examine the armature closely and imagine current entering one of the split rings from a
brush. Trace the path of the current through the wire to the coil, through the coil, through the
Figure 1. Motor Accessory Installed on the Coils and Cores Set
split ring commutator