| Check | Required Condition | |---|---| | | H2‑21 ≤ H2‑22 (Comparator 1) | | Comparator Limits | H2‑27 ≤ H2‑28 (Comparator 2) |
If the coupling between motor and load is loose, or there is excessive gear backlash, the drive’s feedback device (mounted on the motor) will show perfect position, but the actual load position lags. When the load suddenly catches up, the drive perceives it as a latch error.
In Yaskawa’s fault code hierarchy, H66 is not a generic hardware failure. Instead, it is a , often related to the drive’s closed-loop vector control or PM (Permanent Magnet) motor control algorithms.
If you need help tailoring this to your specific system, please let me know: yaskawa error code h66
Third-party encoders often have different line driver characteristics (RS-422 vs open collector). Mismatches cause noise and H66.
Troubleshooting Yaskawa Error Code H66: Causes, Fixes, and Prevention
If the error persists, check the physical connections. Ensure the drive is fully powered down and discharged. Remove the front cover of the VFD. | Check | Required Condition | |---|---| |
If the handheld or mounted digital operator is not seated correctly, the drive may trigger a communication fault.
Suggested temporary mitigations
Navigate to the following parameters using the digital operator: Instead, it is a , often related to
Scan the project for any block calculations involving variable denominators. Ensure logic guards are in place to prevent a value of zero from entering a division block.
Possible causes (ranked)
On most modern Yaskawa VFD platforms—such as the GA700, GA500, A1000, and U1000 series—.