What causes Siemens SINUMERIK alarm 4111?

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 4111?

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.

axismd.ai

Siemens SINUMERIK Controller

PLC · Intermediate · 30-120 minutes

Alarm 4111

Siemens 840D 4111 - PLC cycle increased to ms

Alarm 4111 fires when MD 10074 (PLC_IPO_TIME_RATIO) is set to a non-integer multiple of the IPO cycle divisor, causing the system to automatically recalculate and increase the PLC cycle time. This typically occurs after PROFIBUS DP configuration changes or manual parameter edits that violate the synchronization requirement between PLC and IPO cycle timing.

Siemens SINUMERIKPLCIntermediate30-120 minutes

4111

Siemens 840D 4111 - PLC cycle increased to ms

PLC cycle increased to ms

Root Cause Summary

Alarm 4111 fires when MD 10074 (PLC_IPO_TIME_RATIO) is set to a non-integer multiple of the IPO cycle divisor, causing the system to automatically recalculate and increase the PLC cycle time. This typically occurs after PROFIBUS DP configuration changes or manual parameter edits that violate the synchronization requirement between PLC and IPO cycle timing.

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Causes and Fixes

1
Access Diagnostics > Parameters > MD 10074 on the HMI. Record current PLC_IPO_TIME_RATIO value.
2
Check MD 10050 (SERVO_CYCLE_TIME_RATIO) or equivalent IPO cycle base. The PLC cycle must be a multiple of this value.
Do not modify these values without full understanding of system timing requirements.
3
Recalculate valid PLC_IPO_TIME_RATIO values: typical ratios are 1, 2, 4, 8, or 16 depending on the IPO base cycle. Set MD 10074 to a confirmed integer multiple.
4
Save parameters (MD), perform warm restart (Cycle Start → System → Restart), and verify alarm 4111 does not recur.

Service Recommended confidence

Seeing Multiple Alarms?

Seeing another alarm with this one? Enter the code.

Get machine-aware diagnosis

AxisMD logs alarms against your actual machines, tracks patterns, and gives AI context your manual doesn't have.

Start free

Was this guide helpful?

Always verify with your machine manual or a certified technician before performing service procedures.