What causes Siemens SINUMERIK alarm 10243?

NC program still executing in another channel of the machine. Mode change requested while interpolation or motion is active in paired channel. Improper sequence of mode change commands between synchronized channels. Channel synchronization logic preventing mode transition until all channels reach compatible state.

How do I fix Siemens SINUMERIK alarm 10243?

1. Stop or complete execution of part programs in all other channels before attempting mode change 2. Verify that all motion commands have finished and axes are in a stable state across all channels 3. Check channel synchronization settings and ensure channels are properly configured for independent or dependent operation as required 4. Review NC program logic for mode change sequencing; confirm mode changes occur only when all channels are idle or synchronized 5. If issue persists, perform a soft reset of the control and retry the mode change operation

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Siemens SINUMERIK Controller

Servo/Axis · Intermediate · 10-20 minutes

Alarm 10243

Siemens 840D 10243 - [up to SW 3.x only] Channel: mode group cannot change mode

Alarm 10243 occurs when attempting to change the mode of a channel that belongs to a mode group while another channel in the same mode group is still executing NC functions. This is a synchronization conflict where the control system prevents mode changes to maintain operational integrity across linked channels.

Siemens SINUMERIKServo/AxisIntermediate10-20 minutes

10243

Siemens 840D 10243 - [up to SW 3.x only] Channel: mode group cannot change mode

[up to SW 3.x only] Channel: mode group cannot change mode

Root Cause Summary

Alarm 10243 occurs when attempting to change the mode of a channel that belongs to a mode group while another channel in the same mode group is still executing NC functions. This is a synchronization conflict where the control system prevents mode changes to maintain operational integrity across linked channels.

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Causes and Fixes

1
Check all channels assigned to the affected mode group on the HMI and identify which channel is still active or executing.
2
Press the STOP or RESET button on the active channel to halt program execution cleanly.
Do not use emergency stop unless absolutely necessary as it may cause position loss.
3
Wait for the channel status to show 'RESET' or 'IDLE' before attempting the mode change again.
4
If the issue persists, verify mode group configuration in MD28082 (MM_NUM_CHAN_IN_MODEGROUP) and ensure channels are properly synchronized.

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