Speed feedback configuration

What does A797 mean?

The speed feedback configuration has changed or is inconsistent. The auxiliary code provides details on the specific encoder interface module and encoder affected, and the nature of the problem. This can lead to incorrect speed control or motor operation.

• Incorrect encoder type selected in drive parameter P2-01 (Encoder 1 type) or P2-02 (Encoder 2 type) for the physically installed encoder.
• Loss of connection or intermittent signal from the primary speed feedback device (encoder 1) to the drive's encoder interface module.
• Configuration mismatch between the drive's expected encoder resolution (e.g., P2-05) and the actual encoder pulses per revolution.
• Physical damage to the encoder itself, resulting in no pulses or corrupted pulses, despite correct wiring.
• Auxiliary encoder interface module (e.g., FEN-21) has become dislodged or is faulty, preventing proper communication with the drive's control board.

Click steps to track your progress.

1. 1

   Verify the installed encoder's type and resolution, then cross-reference with parameters P2-01 (Encoder 1 type) and P2-05 (Encoder 1 resolution) in the drive. Adjust parameters if necessary.

2. 2

   Inspect all connections of the encoder feedback cable to the drive's encoder interface module (e.g., terminals X1-X8). Measure signal integrity with an oscilloscope if intermittent.

3. 3

   Power cycle the drive and the encoder interface module. Observe if the auxiliary code changes or clears, indicating a transient communication issue.

4. 4

   If a separate encoder interface module is used (e.g., FEN-21), ensure it is securely seated in its slot and check its status LEDs for errors.

5. 5

   With the drive powered off, measure continuity on all encoder cable conductors from the encoder connector to the drive terminals (e.g., X1-X8) to detect breaks.