202 YASKAWA TM.V1000.01 V1000 Drive Installation & Start-Up Manual (Preliminary 01-19-07)5.5 Fault Detection5.5 Fault DetectionWhen the drive detects a fault, the digital operator displays the fault information,the fault contact closes, and the motor coasts to a stop. However, a fault that has aselectable stopping method will operate according to that stopping method.Investigate the cause of a fault and refer to Table 5.9 for the appropriate action.To restart, reset the fault with one of the following procedures:• Set “14: Fault Reset” to a multi-function digital input (H1-01 to H1-06). Then,close and open the input.• Press the RESET button of the digital operator.• Shut off the drive input power and then turn on again.◆ Fault Displays, Causes, and Possible SolutionsTable 5.9 Detailed Fault Displays, Causes, and Possible SolutionsLED Operator Display Fault NamebUSOption Communication Error• After establishing initial communication, the connection was lost.• Only detected when the run command frequency reference is assigned to anoption card.Cause Possible SolutionNo signal is being received from thePLC. • Check for faulty wiring.• Correct the wiring.• Check for loose wiring and short circuits. Repair as needed.The communication cable is faultyor a short circuit exists.A communications data erroroccurred due to noise.• Check the various options available to minimize the effects of noise.• Take steps to counteract noise in the control circuit wiring, main circuit linesand ground wiring.• Ensure that other equipment such as switches or relays do not cause noise anduse surge suppressors if required.• Use cables recommended by Yaskawa or another type of shielded line.Ground the shield on the controller side or on the drive input power side.• Separate all wiring for communications devices from drive input power lines.Install a noise filter to the input side of the drive input power.The option card is damaged. • Replace the option card if there are no problems with the wiring and the errorcontinues to occur.The option card is not properlyconnected to the drive.• The connector pins on the option card are not properly lined up with theconnector pins on the drive.• Reinstall the option card.
