Yaskawa Matrix Converter - Manual (Page 342)

Troubleshooting
7-
21
‹ Direction of the Motor Rotation is Reversed
If the motor operates in the wrong direction, the motor output wiring is faulty. When the MxC T1 (U), T2 (V),
and T3 (W) are properly connected to the motor T1 (U), T2 (V), and T3 (W), the motor operates in a forward
direction when a Forward Run Command is executed. The forward direction depends on the manufacturer and
the motor type, so be sure to check the specifications.
The direction of rotation can be reversed by switching two wires among T1 (U), T2 (V), and T3 (W).
‹ Motor Does Not Produce Torque or Acceleration is Slow
Use the following information if the motor does not output torque or if acceleration is too slow.
„ The torque limit has been reached.
When a torque limit has been set in parameters L7-01 to L7-04, no torque will be output beyond that limit.
This can cause the torque to be insufficient, or the acceleration time to be too long. Check to be sure that the
value set for the torque limit is suitable.
If torque limits have been set for the multi-function analog input (H3-05 or H3-09 = 10 to 12 or 15), check to
be sure that the analog input value is suitable.
„ The stall prevention level during acceleration is too low.
If the value set for L3-02 (Stall Prevention Level during Acceleration) is too low, the acceleration time will be
too long. Check to be sure that the set value is suitable.
„ The stall prevention level during run is too low.
If the value set for L3-06 (Stall Prevention Level during run) is too low, the speed will drop before outputting
torque. Check to be sure that the set value is suitable.
„ Auto-Tuning has not been performed for vector control
Open Loop Vector and Flux Vector controls will not work if Auto-Tuning has not been performed first. Per-
form Auto-Tuning separately for the motor, or set the motor parameters through calculations. Alternatively,
change the Control Method Selection (A1-02) to V/f control (0).
‹ Motor Operates Faster than the Frequency Reference
Use the following information if the motor operates faster than the frequency reference.
„ The analog frequency reference bias setting is wrong (the gain setting is wrong).
The frequency reference bias set in parameter H3-03 is added to the frequency reference. Check to be sure that
the set value is suitable.