🏫Learn How I Run Math Groups
Based on Yaskawa's technical guides and field reviews, common triggers for this code include:
: Verify that all emergency stop buttons are released and safety gates are closed.
If the relay outputs are electronic (solid-state semiconductor outputs), ensure that the OSSD (Output Signal Switching Device) pulses are not out of sync. Preventive Maintenance Tips yaskawa error code h66
Temporarily switch from Closed Loop Vector (A1-02 = 2) to V/f Control (A1-02 = 0 or 1). If H66 stops, your encoder or vector tuning is the culprit. You can then re-tune vector control from scratch.
Check the diagnostic LEDs on your external safety relay (e.g., Pilz, Allen-Bradley, or Banner modules). Look for channel fault indicators on the relay itself. Based on Yaskawa's technical guides and field reviews,
indicates that the voltage in the drive's internal DC bus has exceeded the overvoltage detection level. For 200 V class drives, this safety trip triggers when the DC bus reaches approximately 410 V, while 400 V class drives trip at 820 V.
If you recently replaced either the main control board or an option card, their firmware versions might not match. The drive cannot interpret the data structure of an incompatible card. 4. Failed Option Card or Control Board Hardware If H66 stops, your encoder or vector tuning is the culprit
If both functions are genuinely needed, move the inverse output assignment to a different terminal pair that does not also have a secondary function.
The H66 code typically signals an . This means the parameters governing how the drive interprets external analog signals (like those from a potentiometer or a PLC) are logically inconsistent. Common reasons for this include: