Sizing Electric Motor for Motion Control General

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Industrial Electric Motor Application, Design and Installation Menu

To size a electric motor for a particular drive application the designer must first analyze the mechanics of the drive application.  The following must be determined:

  • Friction of the bearings, or other mechanical elements.
  • The weight or load to be driven by the electric motor.
  • Inertia of the mass to be moved or controlled.  Acceleration and deceleration forces should be analyzed.
  • Mechanical system type and number of linkages.

Friction -The friction may be determined by estimation, component specification or by measuring by use of a torque reading device or mechanism.

Weight or Mass - The mass may be calculated using 3D CAD, specification or direct measurement.

Inertia - Inertia is the force  required to accelerate or decelerate a mass.  Inertia is used to calculate the motor torque required to operate the mechanical system.

Mechanical System - There are roughly four categories of mechanical drive systems

  • Direct drive
  • Gear drive
  • Tangential drive
  • Lead-screw or worm-gear