Beckhoff TwinCAT 3 (XAR/XAE) with EtherCAT fault ADS 1798: Invalid data values (0x706, ADSERR_DEVICE_INVALIDDATA)
Beckhoff: invalid data values. The server received a request of the right size but rejected the content, for example a value outside what the service accepts.
Diagnose this with AI
Try Free PLC Fault Diagnostic Upload a keypad photo, the fault history or a parameter export from your Beckhoff TwinCAT 3 (XAR/XAE) with EtherCAT. InduQT compares the evidence and suggests the next useful checks.
When it happens
- On ADS writes or read-writes from a client or the PLC
Likely causes and checks
1Value written is outside the range the server accepts
- Points to it
- Error only for certain values; same write with other values works.
- Check
- Check the documented value range of the index group or parameter being written.
2Request structure filled wrongly by the client
- Points to it
- Every write of that service fails; client library or code recently changed.
- Check
- Capture the request (ADS Monitor or Wireshark) and compare it with the service specification.
Telling it apart
- ADS 1797 is a size problem; 1798 is the content; 1803 (0x70B) is "invalid parameter values" in the service parameters rather than the data.
Evidence to collect
- Exact request: port, index group/offset, length and data
- Value range from the device documentation
- Client code or library version
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