n
Motor Will Not Accelerate or the Acceleration Time is Too Long
Cause
Possible Solutions
Frequency reference is too low.
• Check the maximum output frequency (E1-04).
• Increase E1-04 if it is set too low.
Check U1-01 for proper frequency reference.
Check if a frequency reference signal switch has been set to one of the
multi-function input terminals.
Check for low gain level set to terminal A1 (H3-03).
Load is too heavy.
• Reduce the load so that the output current remains within the
motor-rated current.
• In extruder and mixer applications, the load will sometimes increase as
the temperature drops.
Check if the mechanical brake is fully releasing as it should.
Acceleration time has been set too long.
Check if the acceleration time parameters have been set too long (C1-01,
-03).
Motor characteristics and drive parameter
settings are incompatible with one another
in V/f Control.
• Set the correct V/f pattern so that it matches the characteristics of the
motor being used.
• Check the motor data and adjust V/f pattern settings.
Incorrect frequency reference setting.
• Check the multi-function analog input settings.
• Ensure the analog input value is set to the right value (U1-13).
The Stall Prevention level during
acceleration and deceleration set too low.
• Check the Stall Prevention level during acceleration (L3-02).
• If L3-02 is set too low, acceleration will take a fair amount of time.
• Increase L3-02.
The Stall Prevention level during run has
been set too low.
• Check the Stall Prevention level during run (L3-06).
• If L3-06 is set too low, speed will drop as the drive outputs torque.
• Increase the setting value.
n
Drive Frequency Reference Differs from the Controller Frequency
Reference Command
Cause
Possible Solutions
The analog input frequency gain and bias
are set to incorrect values.
Check the frequency reference terminal input gain level assigned to terminal
A1 (parameter H3-03).
n
Poor Speed Control Accuracy
Cause
Possible Solutions
Slip compensation function disabled or
set up incorrectly.
Adjust the slip compensation gain (C3-01).
5.8 Troubleshooting without Fault Display
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YASKAWA ELECTRIC TOEP C710606 25D YASKAWA AC Drive J1000 Installation & Start-Up Manual
