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Selection calculation motor

Motor Selection Formula
The following explains the required formulas for controlling a stepping motor or servo motor based on pulse signal.
Operation pattern

    f1: Starting pulse speed [Hz]
    f2: Operating pulse speed [Hz]
    A: Number of working pulses
    t0: Positioning time [s]
    t1: Acceleration (deceleration) time [s]
    You can ask us to select the motor you need via home page. You can select what you need through online motor sizing application. More details can be found here.
    Formula of the Number of for Operating Pulses A [Pulse] The number of operating pulses is expressed as the number of pulse signals that add up to the angle that the motor must rotate to get the load from point A to point B.

    ∫: Traveling amount between the from A to B point [m]
    ∫REV: Traveling amount per rotation [m/rev]
    ΘS: step angle [°]
    Formula for Operating Pulse f2 [Hz]
    The speed of operating pulse speed can be obtained from the number of operating pulses, the positioning time and the acceleration (deceleration) time.
    ① For Acceleration/deceleration operation
    The level of acceleration (deceleration) time is an important point in the selection. The acceleration (deceleration) time cannot be set easily, because it correlates with the acceleration torque and acceleration/deceleration rate. Initially, as a reference, calculate the acceleration (deceleration) time at roughly 25% of positioning time. (The calculation must be adjusted before the final decision can be made.)
    ② For Start/stop operation
Formula of the Acceleration/Deceleration Rate TR[ms/kHz]
    The acceleration/deceleration rates are the setting value used for the Oriental Motor's controllers. The acceleration/deceleration rate indicates the degree of acceleration of pulse speed and is calculated using the formula shown below.
    Calculate the pulse speed in full step conversion. For this formula, the speed is in [kHz] and the time in [ms].
Conversion formula for the Operating Speed NM [r/min] from the Operating Pulse Speed f2 [Hz]
Formula for the Acceleration of torque Ta[N・m]
    In the motor speed is varied, the acceleration torque or deceleration torque must be set. The basic formula is the same for all motors. However, use the formulas below when calculating the acceleration for stepping motors on the basis of pulse speed.
    Common basic formula for all motors

    J0: Rotor inertia[kg·m2
    JL:Total load inertia [kg·m2]
    NM : Operating speed [r/min]
    t1: Acceleration (deceleration) time [s]
    i: Gear ratio

    < When calculating the acceleration torque for steeping motors on the basis of pulse speed>
    ①Acceleration/deceleration operation

    ②Start/stop operation
Formula for the Required Torque TM[N・m]

    TM :Required torque[N·m] TL : : Load torque N·m] Ta : Acceleration torque[N·m] Sf : Safety factor
Formula for the Effective Load Torque Trms[N・m]
    Calculate the effective load torque when selecting the servo motor and BX Series brushless motors. When the required torque for the motor varies over time, determine if the motor can be used by calculating the effective load torque. The effective load torque becomes particularly important for operating patterns such as fast-cycle operations where acceleration/deceleration is frequent.