Beckhoff TwinCAT 3 (XAR/XAE) with EtherCAT fault ADS 18: Port disabled (0x12, ERR_PORTDISABLED)
Beckhoff: port disabled – TwinCAT system service not started. The ADS router on that machine is not running, so no ADS port can be reached.
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
- After a PC boot, before the TwinCAT system service has started
- When TwinCAT runtime is stopped or failed to start
Likely causes and checks
1TwinCAT system service stopped or not yet started
- Points to it
- Error right after booting; TwinCAT SysTray icon not running.
- Check
- Check the TwinCAT system service state on the machine that returns the error.
2Runtime failed to start (e.g. real-time not available on this PC)
- Points to it
- Logger or Windows events show TwinCAT start errors.
- Check
- Read the logger and Windows event log for TwinCAT start errors on that machine.
Telling it apart
- ADS 18 is about the local router/service; ADS 6 means the service runs but the addressed port has no server.
- Often seen on the client PC itself: an HMI on a PC whose own TwinCAT/ADS router is not running gets ADS 18 for every request.
Evidence to collect
- TwinCAT service state and SysTray status
- Logger and Windows event log at boot
- Which machine returns the error (client or target)
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