Model 6210 Maintenance Manual Electrical Components
DC Motors, General NOTE: For replacement parts information refer to the Parts Manual.
Motor Brush Inspection Figure 7-72.
Motor Brush, Typical Location
Section 7. Component Procedures DC Motors, General 3. Clean brushes and holders. Wipe the commutator with a dry, lint-free cloth. DO NOT USE lubricants of any kind on or around the commutator. 4. Check brush holders for solid connection to the mounting support. Tighten the mounting screws as necessary. 5. Check the cap screws holding the brush cross connectors to the brush holder body. 6. Make sure the motor terminals are secured tightly to the motor frame. Be careful not to strip the threads or crush the insulating parts. 7. Check all the cap screws around the frame for tightness. 8. Keep the outside frame of the motor clean and free from dirt. Maintain a free air passage around the motor to permit heat radiation.
Motor Brush Replacement Conduct a partial inspection of the motor after every 1,000 hours of truck operation. If you work in an abnormally severe or caustic environment or if you have a rigorous duty cycle, inspect the motor more frequently. Set up and rigidly adhere to a strict inspection schedule to obtain the maximum efficiency from the electrical equipment. Each partial inspection of the motor must include the following: 1. Inspect the brushes for wear and for correct contact with the commutator. Record the level of wear on the brushes. This history gives you an indication of whether a brush must be changed or if it can wait until the next inspection. Refer to page 7-60 for acceptable brush length and general motor information. NOTE: Overloading a unit is ultimately reflected in the motor and brush wear; therefore, you must take this into account when considering brush replacement.
If one brush needs replacement, always replace the entire set of brushes. Use only genuine Raymond brushes. Using another type of brush could damage the commutator or cause excessive brush wear. If the end of the brush is not already contoured to fit the commutator, use the following procedure to seat the brush to the commutator. NOTE: If the motor commutator is not accessible, form the brush contour using a brush seating stone. 1. Move the motor brush springs out of your way. 2. Wrap a piece of 00 sandpaper around the commutator. DO NOT use emery cloth to seat brushes. 3. Move the brushes back down in their holders so that the face of the brushes matches the curve of the commutator. 4. Remove the sandpaper.
2. Check brush spring tension. See “Motor Brush Spring Tension” on page 7-60.
5. Blow any dust out of the motor with clean, compressed air at a maximum of 30 psi (207 kPa).
Publication: 1146947, Revised: 12 Jan 2017
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