YASKAWA A1000 Series Quick Start Manual

Also see for A1000 Series: Installation manual Technical manual Quick start guide Technical manual Manual

Contents

5 TroubleshootingYASKAWA ELECTRIC TOEP C710616 21C YASKAWA AC Drive - A1000 Quick Start Guide 107Troubleshooting5ovOvervoltageVoltage in the DC bus has exceeded the overvoltage detection level.• For 200 V class: approximately 410 V• For 400 V class: approximately 820 VCause Possible SolutionDeceleration time is too short andregenerative energy is flowing from themotor into the drive.• Increase the deceleration time (C1-02, C1-04, C1-06, C1-08).• Install a dynamic braking option.• Enable stall prevention during deceleration (L3-04 = 1).Stall Prevention is enabled as the default setting.Fast acceleration time causes the motor toovershoot the speed reference.• Check if sudden drive acceleration triggers an overvoltage alarm.• Increase the acceleration time.• Use longer S-curve acceleration and deceleration times.• Enable the Overvoltage Suppression function (L3-11 = 1).• Lengthen the S-curve at acceleration end.Excessive braking load. The braking torque was too high, causing regenerative energy to charge the DC bus. Reduce thebraking torque, use a dynamic braking option, or lengthen decel time.Surge voltage entering from the drive inputpower.Install a DC reactor.Note: Voltage surge can result from a thyristor convertor and phase advancing capacitor using thesame input power supply.Ground fault in the output circuit causingthe DC bus capacitor to overcharge.• Check the motor wiring for ground faults.• Correct grounding shorts and turn the power back on.Improper Setting of Speed Search relatedparameters. (Includes Speed Search after amomentary power loss and after a faultrestart.)• Check the settings for Speed Search-related parameters.• Enable Speed Search restart function (b3-19 greater than or equal to 1 to 10).• Adjust the current level during Speed Search and the deceleration time (b3-02 and b3-03respectively).• Perform Stationary Auto-Tuning for line-to-line resistance and then enable Speed EstimationSpeed Search (b3-24 = 1).Drive input power voltage is too high. • Check the voltage.• Lower drive input power voltage within the limits listed in the specifications.The braking transistor is wired incorrectly. • Check braking transistor wiring for errors.• Properly rewire the braking resistor device.PG cable is disconnected. Reconnect the cable.PG cable wiring is wrong. Correct the wiring.Noise interference along the PG encoderwiring. Separate the wiring from the source of the noise (often the output lines from the drive).Drive fails to operate properly due to noiseinterference.• Review the list of possible solutions provided for controlling noise.• Review the section on handling noise interference and check the control circuit lines, main circuitlines, and ground wiring.Load inertia has been set incorrectly.• Check the load inertia settings when using KEB, overvoltage suppression, or Stall Preventionduring deceleration.• Adjust the load inertia ratio in L3-25 to better match the load.Braking function is being used in OLV/PM. Connect a braking resistor.Motor hunting occurs.• Adjust the parameters that control hunting.• Set the gain for Hunting Prevention (n1-02).• Adjust the AFR time constant (n2-02 and n2-03).• Adjust the speed feedback detection suppression gain for PM motors (n8-45) and the time constantfor pull-in current (n8-47).Digital Operator Display Fault NamePFInput Phase LossDrive input power has an open phase or has a large imbalance of voltage between phases. Detectedwhen L8-05 = 1 (enabled).Cause Possible SolutionThere is phase loss in the drive input power. • Check for wiring errors in the main circuit drive input power.• Correct the wiring.There is loose wiring in the drive inputpower terminals.• Ensure the terminals are tightened properly.• Apply the tightening torque as specified in this manual. Refer to Wire Gauges and TighteningTorque on page 35There is excessive fluctuation in the driveinput power voltage.• Check the voltage from the drive input power.• Review the possible solutions for stabilizing the drive input power.There is poor balance between voltagephases. • Stabilize drive input power or disable phase loss detection.