MATTHIESEN Magic Finger Bagger, Руководство пользователя

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Section 1
General Information
Maintenance & Troubleshooting 3-7 MN605
Commutator
After several hours of operation, the commutator surface under the brush should take on
a darker bronze color. This is due to self-generated film caused by normal commutation.
This coloration should be even, without blotches or black areas. A shiny copper color or
black streaks in the brush tracks are signs of improper commutation or contamination by
a foreign material. Contact Baldor for assistance in correcting these problems.
If the commutator becomes rough and burned, or becomes black, it should be cleaned of
dirt and carbon particles. This can be done by wiping it with a dry, lint-free cloth. Also
vacuuming or blowing out the motor with a dry air supply are suitable cleaning methods.
Do not use solvents or cleaning solutions on the commutator . To remove spots or
contamination that will not wipe off, wrap a strip of coarse (60# grit) sandpaper around
the commutator. Then rotate the armature back and forth by hand. Do not use emery
cloth as this contains electrically conductive materials .
Another method of commutator resurfacing is to use a commercially available
commutator dressing stone. This should only be done by trained and experienced
people. This stone should be taped or attached to the end of a stick made of electrically
insulated material. The motor should be run at about half speed and the stone applied
lightly to the commutator surface. This operation must be done with no load on the motor.
The surface of the commutator should be smooth and round. This can be checked while
the motor is running at low speed. Press lightly on one brush with an insulated stick. Do
not use a lead pencil as this contains electrically conductive graphite . If you feel
movement of the brush, it suggests a worn or uneven commutator. The armature must be
removed from the motor and the commutator machined by a qualified repair shop.
Rapid Commutator Wear
Light electrical loads and contamination are the usual causes of rapid commutator wear.
Light loading may require the removal of some brushes on motors with multiple brushes
per pole. Sometimes a low current density brush grade is used. There are also brushes
that have a mild polishing action. These prevent certain chemicals, especially chlorine
and silicone, from attacking the commutator. Brushes, are available for use in plastic
extruder applications where PVC is present. Usually, you do not have to change the
design or grade of the brushes on new motors unless special operating conditions exist.
Do not change brush grades or the number of brushes per pole. Doing so may void the
warranty and make the motor unsafe. Contact your local Baldor district office or an
authorized Baldor service center for technical assistance.
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