Yaskawa Matrix Converter - Manual (Page 319)

6
-154
„ Analog Input Filter Time Constant
If noise enters the analog frequency reference during run using analog frequency reference (b1-01 = 1), and
operation becomes rough, implement noise countermeasures and also set H3-12 (Analog Input Filter Time
Constant) to between 0.01 and 0.10 s.
‹ Confirming Start Up Current and Reducing Carrier Frequency
When performing test run, check the motor current using the digital operator or a clamp ammeter with and
without the load. An extremely high current will flow if the motor torque at start is insufficient, or if timing is
not correct and the motor locks with the holding brake.
If the current at start is 150%, the IGBT in the MxC will be subject to heat stress, resulting in a shortened per-
formance life. Refer to the previous precautions and take steps to reduce the current, such as re-tuning and
reducing the load until the current drops to less than 150%. If using Flux Vector Control and particularly low
noise is not required, reduce the influence of heat stress by decreasing the MxC’s carrier frequency to 4 kHz.
IMPORTANT
1. For either increasing or decreasing torque, externally maintain the torque compensation signals during run
to prevent them from fluctuating. Fluctuation in compensation signals during run may result in oscillation.
2. If reverse run is used for lifting and forward run is used for lowering, the torque compensation signal polar-
ity must be reversed.