LED Operator Display Fault NameoPrExternal Digital Operator Connection Fault• The external operator has been disconnected from the drive.Note: An oPr fault will occur when all of the following conditions are true:• Output is interrupted when the operator is disconnected (o2-06 = 1).• The run command is assigned to the operator(b1-02 = 0 and LOCAL has been selected).Cause Possible SolutionExternal operator is not properly connectedto the drive.• Check the connection between the operator and the drive.• Replace the cable if damaged.• Turn off the drive input power and disconnect the operator. Next reconnect the operator and turnthe drive input power back on.LED Operator Display Fault NameoS Overspeed (Simple V/f with PG)Pulse input (RP) indicates that motor speed feedback exceeded F1-08 setting.Cause Possible SolutionOvershoot or undershoot is occurring.• Adjust the gain by using the pulse train input parameters (H6-02 through H6-05).• Increase the settings for C5-01 (Speed Control Proportional Gain 1) and reduce C5-02 (SpeedControl Integral Time 1).Incorrect PG pulse settings. Set the H6-02 (Pulse Train Input Scaling) = 100%, the frequency of the PG pulses at maximum motorspeed.Inappropriate parameter settings. Check the setting for the overspeed detection level and the overspeed detection time (F1-08 and F1-09).LED Operator Display Fault NameovOvervoltageVoltage in the DC bus has exceeded the overvoltage detection level.• For 200 V class: approximately 410 V• For 400 V class: approximately 820 V (740 V when E1-01 is less than 400)Cause Possible SolutionDeceleration time is too short andregenerative energy flows from the motorinto the drive.• Increase the deceleration time (C1-02, -04, -06, -08).• Install a braking resistor or a dynamic braking resistor unit.• 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.Excessive braking load. The braking torque was too high, causing regenerative energy to charge the DC bus.Reduce the braking torque, use a braking option, or lengthen decel time.Surge voltage entering from the drive inputpower.Install a DC reactor.Note: Voltage surge can result from thyristor convertor and phase advancing capacitor using samedrive main input power supply.Ground fault in the output circuit causing theDC 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 Retry 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 Line-to-Line Resistance Auto-Tuning and then enable Speed Estimation Type SpeedSearch (b3-24 = 1).Excessive regeneration when overshootoccurs after acceleration.• Enable the Overvoltage Suppression function (L3-11 = 1).• Lengthen the S-curve at acceleration end.Drive input power voltage is too high. • Check the voltage.• Lower drive input power voltage within the limits listed in the specifications.The dynamic braking transistor is damaged. Replace the drive.The braking transistor is wired incorrectly. • Check braking transistor wiring for errors.• Properly rewire the braking resistor device.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 Prevention duringdeceleration.• Adjust L3-25 (Load Inertia Ratio) in accordance with the load.6.4 Fault Detection262 YASKAWA ELECTRIC SIEP C710606 16C YASKAWA AC Drive – V1000 Technical Manual
