YASKAWA V1000 Technical Manual page 283

n Motor Stalls During Acceleration or With Large Loads
Cause
Load is too heavy.
n Motor Will Not Accelerate or the Acceleration Time is Too Long
Cause
Frequency reference is too low.
Load is too heavy.
The torque limit function is
operating in Open Loop Vector
Control.
Acceleration time has been set
too long.
Motor characteristics and drive
parameter settings are
incompatible with one another in
V/f Control.
The right combination of motor
characteristics have not been set
in Open Loop Vector Control.
Incorrect frequency reference
setting.
The Stall Prevention level during
acceleration and deceleration set
too low.
The Stall Prevention level during
run has been set too low.
Although the drive is operating in
Open Loop Vector motor control
method, Auto-Tuning has not
been performed.
Drive reached the limitations of
the V/f motor control method.
n Drive Frequency Reference Differs from the Controller Frequency Reference Command
Cause
The analog input frequency gain and bias are set to
incorrect values.
A frequency bias signal is being entered via analog
input terminals A1 or A2.
YASKAWA ELECTRIC SIEP C710606 16C YASKAWA AC Drive – V1000 Technical Manual
Take the following steps to resolve the problem:
• Reduce the load.
• Increase the acceleration time.
• 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 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 terminals A1 or A2 (H3-03, H3-11).
• 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.
• Check the torque limit setting. It may be too low. (L7-01 through L7-04).
• Reset the torque limit to its default value (200%).
Check if the acceleration time parameters have been set too long (C1-01, -03, -05, -07).
• Set the correct V/f pattern so that it matches the characteristics of the motor being used.
• Check E1-03 (V/f Pattern Selection).
Execute Rotational Auto-Tuning.
• Check the multi-function analog input settings.
• Check if multi-function analog input terminal A1 or A2 is set for frequency gain (H3-02 or H3-10 = "1"). If
so, the frequency reference will be 0 if there is no voltage (current) input provided.
• Ensure H3-02 and H3-10 are set to the proper values.
• Ensure the analog input value is set to the right value (U1-13, U1-14).
• 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.
• 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.
• Perform Auto-Tuning.
• Calculate motor data and reset motor parameters.
• Switch to the V/f motor control method (A1-02 = "0").
• The motor cable may be long enough (over 50 m) to require Auto-Tuning for line-to-line resistance.
• Be aware that V/f Control is comparatively limited when it comes to producing torque at low speeds.
• Consider switching to Open Loop Vector Control.
• Check the main speed frequency reference terminal input gain level assigned to terminals
A1 and A2, as well as the frequency reference input bias to terminals A1 and A2 (parameters
H3-03, H3-04, and H3-12).
• Set these parameters to the appropriate values.
• If multi-function analog input terminals A1 and A2 are set for frequency reference (H3-02
= 0 and H3-10 = 0), the addition of both signals builds the frequency reference.
• Ensure that H3-02 and H3-10 are set appropriately.
• Check the input level set for terminals A1 and A2 (U1-13, U1-14).
6.9 Troubleshooting without Fault Display
Possible Solutions
Possible Solutions
Possible Solutions
6
283