CoF

Current Offset Fault

Yaskawa · V1000 AC Drive

What does CoF mean?

This fault occurs if the drive attempts to start operation while residual induced voltage remains in the motor (e.g., during coasting to a stop or immediately after fast deceleration). Additionally, it can signify a drive hardware problem, where the current offset value exceeds the permitted setting range during the drive's automatic adjustment process. If not resolved, this can lead to incorrect motor control or further damage to the drive hardware.

Additional Steps

Steps 1–2 are listed in Priority Fix.

  1. 3

    If the fault persists after addressing sequence adjustments and implementing speed search, assume a drive hardware problem and proceed with replacing the drive unit.

Source: Yaskawa V1000 AC Drive
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