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Toshiba Tosvert VF-AS1 User Manual

Page 151

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E6581301

F-39

6

Examples of setting the motor constants

Here are setting examples for each of the selections 1, 2 and 3 described in Section 6.22.

a) Combination with a Toshiba standard motor (4P motor with the same capacity as the

inverter)

Inverter : VFAS1-2037PL
Motor

: 3.7kW-4P-60Hz

[Selection 1]

Set the automatic torque boost (CW) at .

[Selection 2]

1) Set the V/f control mode selection RV at (Sensorless vector control).
2) Set the auto-tuning 1 (H) at . (When the cable length is 30m or over.)

b) Combination with a standard motor other than the above Toshiba motor

Inverter : VFAS1-2037PL
Motor

: 2.2kW-2P-50Hz

[Selection 1]

Set the automatic torque boost (CW) at .

[Selection 2]

1) Set the V/f control mode selection RV at (Sensorless vector control).
2) Set XN, XNX, H, H and H, as specified on the motor nameplate.
3) Set the auto-tuning 1(H) at .
4) Set the auto-tuning 1 (H) at .

6.23

Increasing the motor output torque further in low speed range

H

: Exciting strengthening coefficient

H

: Stall prevention factor

The output torque of the motor can adjusted using the parameters described in 6.22 in most cases, but if a finer
adjustment is required, use these parameters.

[Parameter setting]

Title

Function

Adjustment range

Default setting

H

Exciting strengthening coefficient

~%

H

Stall prevention factor

~

If the torque needs to be increased in low speed range (10Hz or less as a guide)
Perform auto-tuning according to the instructions in 6.22, and if the torque needs to be increased further in low
speed range, first increase the slip frequency gain (H) to a degree (80% or so as a guide) that hunting of the
motor does not occur. Then, increase motor constant 1 (H) by 1.1 times the current value as a guide. If the
torque needs to be increased even further, increase the exciting current factor (H) to a maximum of 130%.
H

is a parameter that increases the magnetic flux of the motor at low speeds, so specifying a higher value for

H

increases the no-load current. If the no-load current exceeds the rated current, do not adjust this parameter.

If the motor stalls when operated at frequencies above the base frequency
Adjust H (stall prevention factor).
If a heavy load is applied momentarily (transiently), the motor may stall before the load current reaches the stall
prevention level (H). In such a case, a motor stall may be avoided by reducing the value of H gradually.