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.

Complete Troubleshooting Guide

1. 1

   Check the wiring connections for analog input AI3 at both the drive and the signal source.

2. 2

   Verify the 4-20 mA signal source (e.g., sensor, PLC) is operational and outputting correctly.

3. 3

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

4. 4

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