AI3 4-20mA Loss

What does LFF3 mean?

Loss of the 4-20 mA signal on analog input AI3. This input is typically used for speed reference, feedback, or other critical process values. Loss of this signal will cause the drive to lose its reference, potentially leading to a stop or uncontrolled operation.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Measure the current loop at AI3 terminals to confirm signal presence (expect 4-20mA).

2. 4

   Ensure the drive's AI3 input settings (e.g., scale, filtering, fault behavior) are correctly configured.