Overview of Inverter Selection Selecting the Inverter Capacity • Calculating the Combined Torque and Effective Torque Effective torque: T RMS (N m) Select an Inverter that is large enough to handle the motor selected in Selecting the Motor above. Basically, select an Inverter with a maximum motor capacity that matches the motor capacity calculated above. After selecting the Inverter, verify that the following conditions are satisfied. If the conditions are not satisfied, select the Inverter that is one size larger and check the conditions again.
• Motor’s rated current ≤ Inverter’s rated output current • The application’s continuous maximum torque output time ≤ 1 minute Selection Features = Σ (Ti) 2 ti = t 1 + t 2 + t 3 + t 4 T 1 t 1 + T 2 t 2 + T 3 t 3 + T 4 t 4 2 2 2 2 Σ ti Maximum torque: T MAX = T 1 = T A + T L (r/min) Speed 0 Acceleration/ Deceleration torque Motor shaft conversion load torque Combined torque (N m) Note 1. If the Inverter's overload endurance is 120% of the rated output current for one minute, check for 0.8 minute. 2.
Use an Inverter that is one size larger than determined by the condi- tions above if open-loop vector control with PG is being used and a holding torque is required at 0 r/min or a torque that is 150% or more of the rated torque is required regularly at low frequencies (10 Hz or less). SYSDRIVE JX Series SYSDRIVE MX Series SYSDRIVE RX Series SYSDRIVE Option 0 (N m) * Use the Servomotor's Motor Selection Software to calculate the motor conversion inertia, effective torque, and maximum torque shown above. ● Selecting the Motor Use the results of the calculations above and the equations below to determine the required motor capacity from the effective torque and maximum torque.
Use the larger of the following motor capacities when selecting the motor. When selecting the motor, set a motor capacity higher than the calculated capacity to provide some extra capacity. • Motor Capacity Supplied for Effective Torque: Motor capacity (kW): 1.048 • N • T RMS • 10 − 4 Overview of Inverter Selection • Motor Capacity Supplied for Maximum Torque: Motor capacity (kW): 1.048 • N • T RMS • 10 − 4 /1.5 (N: Max. speed in r/min) (N: Max. speed in r/min) Overview of Inverter Selection 59 N t1 t2 t3 t4 Time (s 1 cycle T A Time (s TL T 1 T2 T 3 T A