Beckhoff TwinCAT 3 (XAR/XAE) with EtherCAT fault NC 0x4260: Controller enable missing (16992)
Beckhoff: the controller enable for an axis or a coupled slave axis is not present (axis interface PlcToNc). The error occurs if controller enable is withdrawn while an axis or group (also a master/slave group) is being actively positioned, and if a PTP axis or coupled slave axis is started without controller enable.
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
- During a move, when MC_Power Enable drops
- When a move or coupling is started before the axis is enabled
Likely causes and checks
1PLC logic removes enable during a move (e.g. MC_Power Enable tied to a condition that drops)
- Points to it
- Error at the moment the enable condition changes; Scope shows Enable falling while the axis is busy.
- Check
- Trace MC_Power Enable/Status and the move FB Busy in Scope View.
2Move started before MC_Power reported Status = TRUE
- Points to it
- Error at start of motion, not during it.
- Check
- Check the sequence waits for MC_Power.Status before starting moves or couplings.
3Coupled slave axis not enabled
- Points to it
- Master moves, error raised for the group or slave.
- Check
- Check enable on every axis of the coupled group.
Telling it apart
- 0x4356 (axis error "controller enable") is the axis-level counterpart; 0x4357/0x4358 are missing feed enables minus/plus.
- 0x4650 means the drive itself is not ready; 0x4260 means the NC enable from the PLC is missing.
- A safety stop (STO via TwinSAFE) that removes drive enable is intended behaviour; fix the sequence, never bypass the safety function.
Evidence to collect
- Axis online tab (error code, enables, status)
- Scope View trace of MC_Power Enable/Status and move FB Busy/Error
- PLC code of the enable chain
- Logger export
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