4–37

SJ100 Inverter

If the inverter drives a motor/load with a small inertia, the motor may exhibit “hunting” during running. If this occurs, take the following corrective steps:

1.Adjust the stabilization constant H_06/H206.

2.Decrease the carrier frequency B_83, but not below 2.1 kHz.

3.Set the Automatic Voltage Regulation (AVR) function A_81 to the OFF setting (disabled = 01).

If the desired characteristic cannot be obtained in sensorless vector controlled operation with standard (factory default) or auto-tuning data, adjust the motor constant(s) according to the observed symptoms shown below.

Operation Status

Symptom

Adjustment

Parameter

 

 

 

 

 

 

 

 

Powered running

When low frequency (a

Increase the motor speed constant

H_20 / H_30 /

(status with a positive

few Hz) torque is insuffi-

R1 step by step, up to 1.2 times

H220/ H230

torque)

cient

initial value.

 

 

 

 

 

 

When the speed deviation

Increase the motor constant R2

H_21 / H_31 /

 

is negative

step by step, up to 1.2 times initial

H221 / H231

 

 

value.

 

 

 

 

 

 

When the speed deviation

Decrease the motor constant R2

H_21 / H_31 /

 

is positive

step by step, down to 0.8 times

H221 / H231

 

 

initial value.

 

 

 

 

 

Regeneration

When low frequency (a

Increase the motor speed constant

H_20 / H_30 /

(status with a negative

few Hz) torque is insuffi-

R1 step by step, up to 1.2 times

H220/ H230

torque)

cient

initial value.

 

 

 

 

 

 

 

Increase the motor constant Io

H_23 / H_33 /

 

 

step by step, up to 1.2 times initial

H223 / H233

 

 

value.

 

 

 

 

 

Driving or regenerating

Unstable rotation

Decrease the carrier frequency set

B_83

 

 

value.

 

 

 

 

 

Note 1: If the inverter is using sensorless vector control and the motor is more than one frame size smaller than the maximum applicable motor, then the motor characteristic values may not be satisfactory.

Note 2: No sensorless vector control operation is possible if two or more motors are connected (parallel operation).

Note 3: When the auto-tuning function is executed in the state that the DC braking is set, the motor constants will not be accurately set. Therefore, disable DC braking and then start the auto-tuning procedure again.

Note 4: When accelerating or speeding up is not to be performed in the auto-tuning step for accelerating up to 80% of the base frequency, lower the set value of manual torque boost.

Note 5: Be sure the motor is stopped before you carry out an auto-tuning procedure. Auto-tuning data that is derived while the motor is still running may not be correct.

Operations Monitoring and