Motor Stalls During Acceleration Or With Large Loads Or Acceleration Time Is Too Long; Drive Frequency Reference Differs From The Controller Frequency Reference Command - YASKAWA FSDrive-MV1000 Series Instructions For Use Manual

5.11 Troubleshooting without Fault Display
u Motor Stalls During Acceleration or With Large Loads or Acceleration Time is Too
Long
Cause
Torque limit has been reached or current suppression
keeps the drive from accelerating.
Load is too heavy.
Torque limit is not set properly.
Frequency reference is too low.
Load is too heavy.
Acceleration time has been set too long.
Although the drive is operating in vector motor control
method, Auto-Tuning has not been performed.
Incorrect frequency reference setting.
The Stall Prevention level during acceleration set too
low.
The Stall Prevention level during run has been set too
low.
Drive reached the limitations of the V/f motor control
method.
u Drive Frequency Reference Differs from the Controller Frequency Reference
Command
Cause
The analog input gain and bias for the frequency
reference input are set to incorrect values.
A frequency bias signal is being entered via analog input
terminal L1.
PID control is enabled.
186
Take the following steps to resolve the problem:
• Reduce the load.
• Increase motor capacity.
Although the drive has a Stall Prevention function and a Torque Compensation Limit
function, accelerating too quickly or trying to drive an excessively large load can
exceed the capabilities of the motor.
Check the torque limit setting.
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 switch signal has been set to one of the contact input
terminals.
• If analog input is used, check for a low gain level set for terminal L1 (H3-03).
• 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.
• Increase the acceleration time.
• Check if the mechanical brake is fully releasing properly.
Check if the acceleration time parameters have been set too long (C1-01, C1-03, C1-05,
C1-07).
• Perform Auto-Tuning.
• Calculate motor data and reset motor parameters.
• Check the analog input terminal settings.
Analog input terminal L1 is set for frequency gain (H3-02 is set to 1), but there is no
voltage or current input provided.
• Make sure H3-02 is set to the proper value.
• Make sure the analog input value is set to the proper value (U1-13).
• Check the Stall Prevention level during acceleration (L3-02).
• If L3-02 is set too low, acceleration may be taking too long.
• Increase L3-02.
• 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.
• If the motor cable is long (50 m or more), run Auto-Tuning only for Line-to-Line
Resistance.
• Consider switching to vector control mode.
Check the gain and bias settings for the analog inputs that are used to set the frequency
reference. Check parameters H3-03 and H3-04 for input L1.
Set these parameters to the appropriate values.
• The analog input setting (H3-02) is the sum of the individual input values.
• Make sure that H3-02 is set appropriately.
• Make sure that the analog input level is appropriate (U1-13).
If PID control is not necessary for the application, disable it by setting b5-01 to 0.
When PID control is enabled, the drive adjusts the output frequency to match the PID
setpoint. The drive will only accelerate to the maximum output frequency set in E1-04
while PID control is enabled.
YASKAWA ELECTRIC TOEP C710687 02B FSDrive-MV1000 Instructions
Possible Solutions
Possible Solutions