NEMA CB 1:2000 (R2012)

Foreword
Section 1 GENERAL
          1.1 Scope
          1.2 Definition of Brush
          1.3 Classification of Brushes According to Material
          1.4 Classification of Brushes According to Size
          1.5 Classification of Brushes According to Construction
          1.6 Definition of Shunt
          1.7 Definitions of Brush Surfaces
          1.8 Brush Connections
          1.9 Brush Clips
          1.10 Brush Pads
          1.11 Wear Indicators
Section 2 DIMENSIONS AND TOLERANCES
          2.1 Brush Dimensions
          2.2 Order of Brush Surface Dimensions
          2.3 Dimensions - Thickness (Tangential Dimensions),
               Width (Axial Dimension), Length (Radial Dimension),
               and Diameter
          2.4 Tolerances - Thickness (Tangential Dimension), Width
               (Axial Dimension), (Radial Dimension), and Diameter
          2.5 Beveled Ends and Concave Faces
          2.6 Brush Heads
          2.7 Chamfers
          2.8 Holes, Counterbores, and Countersinks
          2.9 Shoulders, Slots, Grooves, and Notches
          2.10 Toes
          2.11 Available Area at Top of Brush for Applying Pressure
          2.12 Shunts
          2.13 Terminations of Brush Shunts for Screw or Bolted
               Connection
          2.14 Termination of Shunts for Brushes to be Used in
               Cartridge-Type Holders
          2.15 Quick Connected Terminals
          2.16 Procedure for Describing Brushes, Including Shunts,
               etc
Section 3 TEST PROCEDURE FOR PHYSICAL PROPERTIES
          3.1 General
          3.2 Scleroscope Hardness
          3.3 Indentation Hardness
          3.4 Resistivity
          3.5 Flexural Strength
          3.6 Density
          3.7 Porosity
          3.8 Ash Content
Section 4 TEST PROCEDURES FOR SHUNT CONNECTIONS
          4.1 General
          4.2 Resistance of Shunt Connections
          4.3 Strength of Type M and Q Shunt Connections
Appendix A Spring Design Information
Appendix B Coil Springs for Brushes
Appendix C Recommended Minimum Clearances Between Brush and
           Brushholder
Appendix D International Electrotechnical Commission (IEC)
           Limits and Tolerances
Appendix E Recommended Width of Pressure Device
Appendix F Brush Voltage Drop and Coefficient of Friction
Appendix G Descriptive Terminology
Appendix H Geometrical Units and Symbols
Appendix I Commutation Surface Conditions
Appendix J Technical Questionnaire

These standards record definitions, dimensions and tolerances, test procedures for physical properties, and test procedures for shunt connections for brushes used in the electrical manufacturing industry.