Yaskawa iQpump Controller User Manual - Manual (Page 154)

6.7 Troubleshooting
154 YASKAWA TM.iQp.06 iQpump Controller User Manual
• Increase the parameter b2-04 (DC Injection Braking (initial excitation) Time at Stop) setting.
• Increase the parameter b2-02 (DC Injection Braking Current) setting.
◆ If Zero Volts are Detected When a Motor is Started or Stalled
Generation of 0 V (main circuit voltage) and stalling can occur if a motor is turning when it is started and the DC injection braking is
insufficient.
This can be prevented by slowing motor rotation by DC injection braking before starting. Increase parameter b2-03 (DC injection braking
time at start) setting.
◆ If the Accepted Speed Command Does Not Rise to the User Speed Command
Input
■
The Speed Command is within the jump frequency range.
When the jump frequency function is used, the output frequency cannot be set within the jump frequency range. Check to be sure that the
Jump Frequency (parameters d3-01 to d3-03) and Jump Frequency Width (parameter d3-04) settings are suitable.
■
The frequency reference upper limit has been reached.
The output frequency upper limit is determined by the following formula:
• Freq Ref Upper Limit = Maximum Output Frequency (E1-04) × Frequency Reference Upper Limit (d2-01) / 100
• Check to be sure that the parameter E1-04 and d2-01 settings are suitable.