12.9 n: SPECIAL
794 SIEPYEUOQ2A01A AC Drive Q2A Technical Manual
• J
Motor
= Moment of inertia of motor (kg m
2
)
• n
rated
= Motor rated speed (min
-1
, r/min)
• T
rated
= Motor rated torque (N m)
You can also use this formula to find the motor acceleration time:
• f
rated
= Motor rated frequency (Hz)
• P = Number of motor poles
Calculate the Motor Acceleration Time
Use this procedure to calculate the motor acceleration time:
1. Use A1-02 [Control Method] to set the control method.
2. Disconnect the motor and load.
3. Run Auto-Tuning to set motor parameters.
When you cannot do Auto-Tuning, manually set motor parameters with the information on the motor
nameplate or test reports. Set the E2 parameters for induction motors. Set the E5 parameters for PM motors.
4. Set C5 parameters [C5: ASR - SPEED REGULATION].
5. Set C1-01 [Accel Time 1] = 0.
6. Set L7-01 [FW Torque Limit] to 100%.
7. Set the frequency reference to the same value as the motor rated speed.
8. Measure the length of time for the motor to reach the rated speed.
Show U1-05 [Motor Speed] on the keypad and enter the Run command (forward run).
9. Stop the motor.
10. Set n5-02 to the measured motor acceleration time value.
Reset all of the parameters that you changed to the previous setting values.
■ n5-03 FF Control Gain
No.
(Hex.)
Name Description
Default
(Range)
n5-03
(05B2)
FF Control Gain
Sets the ratio between load inertia and motor inertia. Inertia Tuning automatically sets the
Feedforward Control Gain value.
1.00
(0.00 - 100.00)
When you cannot do Inertia Tuning, use this procedure to set n5-03:
1. Set n5-02 [Mot Inertia Acceleration Time].
2. Connect the motor and load.
3. Set C1-01 [Accel Time 1] = 0.
4. Use L7-01 to L7-04 [FW Torque Limit to RV Reg. TrqLimit] to set the expected test run torque limit levels.
5. Set the frequency reference as specified by the high speed range of the machine.
6. Measure the length of time for the motor to reach the command reference speed.
Show U1-05 [Motor Speed] on the keypad and enter the Run command.
7. Stop the motor.
8. Replace the values in the this formula and set n5-03 to the value of the formula.
• t
accel
= Acceleration time (s)
• f
rated
= Motor rated frequency (Hz)
• T
Lim_Test
= Test run torque limit (%)
• f
ref_Test
= Test run frequency reference (Hz)
WARNING! Sudden Movement Hazard. Machinery can accelerate suddenly. Do not use this function with machinery that must
not accelerate suddenly. Failure to obey can cause death or serious injury.
To Next Page
Loading...
Need help?
General
