There are parameters such as rated torque, maximum torque and motor inertia in the specifications of each type of motor. There must be a correlation between each parameter and the load torque and load inertia. The output torque of the selected motor should meet the requirements of the load mechanism. Motion condition requirements, such as the speed of acceleration, the weight of the mechanism, the motion mode of the mechanism (horizontal, vertical, rotation), etc.; motion conditions are not directly related to the output power of the motor, but generally the higher the output power of the motor, the relative output torque will also be higher. Therefore, not only the weight of the mechanism will affect the selection of the motor, but the motion conditions will also change the selection of the motor. The larger the inertia is, the larger the acceleration and deceleration torque is required, and the shorter the acceleration and deceleration time is, the larger the motor output torque is. When selecting the servo motor specification, follow the steps below.

(1) Clarify the motion condition requirements of the load mechanism, that is, the speed of acceleration/deceleration, the movement speed, the weight of the mechanism, the movement mode of the mechanism, etc.

(2) According to the requirements of the operating conditions, select the appropriate load inertia calculation formula to calculate the load inertia of the mechanism.

(3) According to the load inertia and motor inertia, select the appropriate hypothetical motor specification.

(4) Calculate the acceleration torque and deceleration torque based on the motor inertia and load inertia that are selected initially.

(5) Calculate the load torque according to the load weight, configuration, friction coefficient and operating efficiency.

(6) The maximum output torque of the primary motor must be greater than the acceleration torque plus the load torque; if the conditions are not met, other models must be selected for calculation and verification until they meet the requirements.

(7) Calculate the continuous instantaneous torque according to the load torque, acceleration torque, deceleration torque and holding torque.

(8) The rated torque of the primary motor must be greater than the continuous instantaneous torque. If it does not meet the conditions, other models must be selected for calculation and verification until it meets the requirements.

(9) Complete the selection.