What causes Siemens SINUMERIK alarm 4007?

Machine data was changed requiring acknowledgment or power cycle. System configuration change notification. Commissioning or service operation generated this notice. Axis or drive configuration change affecting machine data.

How do I fix Siemens SINUMERIK alarm 4007?

1. Read the complete notice text on the SINUMERIK screen. 2. If a power cycle is indicated, perform a controlled machine power off and restart. 3. If machine data backup is indicated, save the current machine data. 4. Acknowledge the notice and verify the system is operating correctly after the change. 5. Consult the machine commissioning engineer if the notice is unexpected.

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Siemens SINUMERIK Controller

Parameter · Intermediate · 30-120 minutes

Alarm 4007

Siemens 840D 4007 - Axis incorrect assignment of master NCU in machine data

Alarm 4007 fires when an axis defined in $MN_AXCONF_LOGIC_MACHAX_TAB (logical machine axis table) for multi-NCU activation is not properly assigned a master NCU via $MA_AXCONF_ASSIGN_MASTER_NCU, or when the master NCU assignment is invalid for single-NCU axes. This creates a logical inconsistency in the NCK configuration where axis ownership and control hierarchy cannot be resolved.

Siemens SINUMERIKParameterIntermediate30-120 minutes

4007

Siemens 840D 4007 - Axis incorrect assignment of master NCU in machine data

Axis incorrect assignment of master NCU in machine data

Root Cause Summary

Alarm 4007 fires when an axis defined in $MN_AXCONF_LOGIC_MACHAX_TAB (logical machine axis table) for multi-NCU activation is not properly assigned a master NCU via $MA_AXCONF_ASSIGN_MASTER_NCU, or when the master NCU assignment is invalid for single-NCU axes. This creates a logical inconsistency in the NCK configuration where axis ownership and control hierarchy cannot be resolved.

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Causes and Fixes

1
Access Siemens SINUMERIK HMI > Diagnosis > Machine Data > $MA_AXCONF_ASSIGN_MASTER_NCU for the affected axis %1. Verify the parameter exists and contains a valid NCU number (1, 2, or 3).
Do not leave this field blank or set to -1; zero is only valid for single-NCU axes.
2
Cross-reference the axis in $MN_AXCONF_LOGIC_MACHAX_TAB to confirm it is activated on multiple NCKs. If activated on only one NCK, set $MA_AXCONF_ASSIGN_MASTER_NCU to that NCK number or 0.
3
Verify the master NCU number matches an active NCK in your configuration. Use HMI > System > NCU Status to confirm NCU IDs are correct (typically NCU1, NCU2 map to parameters 1, 2).
4
Reset the alarm by pressing ESC or STOP, then cycle the control power. The kernel will re-validate axis assignments on startup.

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