How do I fix Siemens SINUMERIK alarm 300950?

1. Please inform the authorized personnel/service department. 2. If no safe automatic referencing is possible, the user must confirm the new position via the softkey. 3. This user confirmation marks this position as safe, that means the axis status "Axis safely referenced" is reached. 4. Warning: If the axis has not been safely referenced and the user has not confirmed, the following applies: - The safe cams are still active and not yet safe. 5. The safe limit positions are not yet active. 6. Alarm display showing cause of alarm disappears. No further operator action necessary

Siemens SINUMERIK codes

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Siemens SINUMERIK Controller

Servo/Axis · Intermediate · 30-120 minutes

Alarm 300950

Siemens 300950 - Axis drive is not safely referenced

This alarm occurs when an axis is not safely referenced or lacks user enable for safety functions. Fix by ensuring proper referencing and enabling safety settings.

Siemens SINUMERIKServo/AxisIntermediate30-120 minutes

300950

Q: What causes Siemens SINUMERIK alarm 300950?

No stop reaction is initiated.. The message will be present during enabling of the functions SN/SE until the axis status "Axis safely referenced" has been reached.. Request: In monitoring cycle..

Siemens 300950 - Axis drive is not safely referenced

Axis drive is not safely referenced

No stop reaction is initiated. The message will be present during enabling of the functions SN/SE until the axis status "Axis safely referenced" has been reached. Request: In monitoring cycle. 1) The axis is not referenced or 2) The user enable for this axis is missing or was canceled. This can occur, for example, if the axis was moved after the machine was switched off and the standstill position which was stored is therefore no longer correct. This message prompts the user to confirm the actual position. To do this, you must determine the position, e.g. as follows: - Measure the position. - Move to a known position Control reaction: Alarm display.

Root Cause Summary

This alarm occurs when an axis is not safely referenced or lacks user enable for safety functions. Fix by ensuring proper referencing and enabling safety settings.

Safety

Drive/power/encoder circuit: hazardous voltages may remain in the DC link after power-off. Lock out / tag out, wait for discharge per the drive documentation, and use qualified personnel only.

Causes and Fixes

1
SAFETY: Ensure machine is in safe state
Verify machine is stopped, all axes are stationary, and work area is clear before proceeding.
2
Check axis status
Verify if the axis is referenced via the control panel or diagnostics screen.
3
Perform referencing
Execute the homing or referencing procedure for the affected axis. Ensure clear path to reference position and no obstructions.
4
Clear alarm and verify
Reset the alarm and verify axis position before resuming operation.

DIY Feasiblemedium confidence

Call a technician if:

·If referencing fails repeatedly
·If safety settings cannot be accessed or modified
·If you lack proper authorization for safety configuration changes
·If axis moves unexpectedly during referencing

Prevention

Always reference axes before running safety-critical programs
Verify safety enables after system resets or updates

Common Mistakes

Skipping axis referencing after power-up
Overlooking safety enable requirements in setup

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