Absolute Encoder EnDat Internal Fault/Error

What does F31111 mean?

The EnDat absolute encoder has detected an internal fault, indicated by set bits in its fault word (r0949). This can include failures such as the lighting system, low signal amplitude, incorrect position values, or issues with the 5V encoder power supply (overvoltage, undervoltage, overcurrent). If the encoder has battery backup, a low battery condition can also trigger this fault. This critical error affects position feedback accuracy and can lead to unreliable drive operation.

• Internal hardware component failure within the EnDat encoder (e.g., lighting system degradation, sensor array malfunction).
• Low signal amplitude detected by the encoder's internal diagnostic system, possibly due to aging or contamination of optical components.
• Incorrect internal position value calculation or CRC (Cyclic Redundancy Check) error within the encoder itself.
• Encoder over-temperature condition, exceeding its specified operating limits due to environmental factors or internal heating.
• Intermittent or unstable internal power supply within the encoder unit, leading to unreliable operation.

Click steps to track your progress.

1. 1

   Access the drive's diagnostic buffer and read register r0949 for the specific fault bits from the EnDat encoder, which indicates the exact internal issue (e.g., low signal, battery, temperature).

2. 2

   Power cycle the machine and observe if the fault clears; transient internal encoder errors can sometimes be reset by a restart.

3. 3

   Verify the supply voltage to the encoder at the encoder connector (e.g., X21) meets the manufacturer's specification (e.g., 5VDC or 24VDC) using a multimeter.

4. 4

   Inspect the encoder and motor mounting for excessive vibration or mechanical stress that could accelerate internal wear or cause misalignment.

5. 5

   If the fault persists after power cycling and supply voltage verification, plan for replacement of the EnDat absolute encoder.