If you wish the drive to ignore the loss of the digital operator (e.g., in remote or permanently installed systems), check parameter:
Changing o2-04 to 1 allows operation without a keypad but will not fix an intermittent H66 caused by noise or hardware failure.
In Yaskawa’s fault code hierarchy, H66 is not a generic hardware failure. Instead, it is a performance-based fault, often related to the drive’s closed-loop vector control or PM (Permanent Magnet) motor control algorithms. yaskawa error code h66
Specifically, H66 indicates that the drive has detected an excessive overshoot or latch detection error during a positioning sequence or speed regulation. In practical terms, the motor did not stop or accelerate as commanded; it overshot the target position or speed, and the drive’s internal feedback monitoring system triggered the alarm to prevent mechanical damage or loss of control.
Go into the motor setup parameters (T1, E1, E2). Compare the motor nameplate values with stored parameters. If you wish the drive to ignore the
If these are off by more than 10%, re-run autotuning with the motor completely uncoupled from the load.
To reset an H66 fault:
Note: If
H66returns immediately after reset or within minutes of operation, the fault is likely a hardware failure.
If you have exhausted all the steps above and H66 persists, professional intervention is needed. Contact Yaskawa support with the following ready: Changing o2-04 to 1 allows operation without a
Yaskawa’s engineering team can provide a custom parameter file or identify a hardware defect (e.g., failed current sensor).