Permanent high level in data line

What does F13.17 mean?

The data signal from Encoder 1 is persistently at a high level. This typically points to a wiring problem (e.g., short to supply voltage) or a defect within the encoder unit, resulting in lost or incorrect position feedback and impacting precise drive control.

• Partial or intermittent short circuit between the encoder data line and the +24VDC supply voltage.
• Degraded internal pull-down resistor within the encoder's data output stage, failing to pull the line low.
• Accumulated moisture or contaminants in the encoder connector causing a resistive path to the supply.
• Faulty input stage on the drive's encoder interface, unable to correctly read the data line's low state.
• Cable insulation breakdown allowing intermittent contact with a supply voltage line.

Click steps to track your progress.

1. 1

   With the encoder disconnected, measure the voltage on the affected data line terminal (e.g., X10/Data+) on the drive's side; it should not be consistently high.

2. 2

   Visually inspect the encoder connector and cable for signs of moisture, corrosion, or physical damage, especially near splice points.

3. 3

   Perform a resistance test on the encoder cable between the data line and the +24VDC wire, looking for low resistance values (e.g., below 10 kOhms).

4. 4

   Clean the encoder connector pins using approved electrical contact cleaner and ensure they are dry before reconnection.

5. 5

   Temporarily replace the encoder cable with a shorter, shielded test cable to rule out cable issues.