27005

Check HMI Operating Mode

Navigate to the HMI main screen and verify the current operating mode display. Look for 'DRY RUN' or dry run symbol in the mode selection area.

The dry run mode icon typically shows a crossed-out spindle symbol on SINUMERIK HMIs

Access Mode Selection Menu

Press the 'Mode' softkey or navigate to Machine > Operating Mode menu to access the mode selection screen.

Ensure machine is in a safe state before changing operating modes

Deactivate Dry Run Mode

Select 'AUTO' or 'MDA' mode instead of 'DRY RUN' mode. The alarm should clear immediately when dry run mode is deselected.

Verify Mode Change

Confirm the operating mode has changed on the HMI display and that alarm 27005 is no longer active in the alarm buffer.

Check PLC Interface Status

Navigate to Diagnostics > PLC > NCK-PLC Interface and examine DB21.DBX1.6 (Dry Run) signal status to confirm if PLC is activating dry run mode.

Use the online monitoring function to watch the signal state in real-time

Examine External Dry Run Switch

Check the machine control panel for a physical dry run selector switch that may be in the active position, forcing the PLC to set the interface signal.

Review PLC Program Logic

Access the PLC program (STEP7/TIA Portal) and examine the logic that controls DB21.DBX1.6 to identify what conditions are causing the signal activation.

Only qualified PLC programmers should modify PLC code

Clear PLC Dry Run Condition

Address the root cause in the PLC logic or external switch position, then monitor the interface signal to confirm it goes inactive.

Check Channel Machine Data

Navigate to Commissioning > Machine Data > Channel Data and examine MD20110 (DRYRUN_MASK) and related dry run machine data parameters for the affected channel.

Review Startup Parameters

Check the NC startup file and channel initialization parameters for any dry run mode activation commands or G-code that may be forcing this condition.

Examine Setting Data

Access Setting Data menu and look for SD42900 (DRY_RUN_FEED) and related setting data that may indicate forced dry run operation.

Setting data changes take effect immediately, while machine data typically requires a restart

Modify Parameter Configuration

Correct any parameter settings that are forcing dry run mode, ensuring proper access level (manufacturer/service) is available for machine data changes.

Examine Active NC Program

Open the currently loaded NC program in the editor and search for dry run activation commands, custom M-codes, or manufacturer-specific G-codes that may trigger this mode.

Check Program Header

Review the program header and initialization section for any dry run mode activation commands that execute at program start.

Look for comments in the program that may indicate intentional dry run activation

Search for M-Code Definitions

Check the M-code definition table in the PLC program to identify any custom M-codes that may activate dry run mode when called from the NC program.

Modify or Remove Dry Run Commands

Edit the NC program to remove or comment out the dry run activation commands, then reload the program to clear the condition.

Check Safety System Status

Navigate to Diagnostics > Safety and examine all safety interlock states, door switches, and emergency stop conditions that may trigger automatic dry run activation.

Verify Door and Guard Positions

Physically inspect all machine doors, guards, and safety devices to ensure they are properly closed and latched.

Never bypass safety interlocks - address the root safety issue instead

Review Safety PLC Logic

Examine the safety PLC program logic to understand how safety conditions are linked to dry run mode activation through the NCK interface.

Clear Safety Conditions

Address any open safety conditions by properly closing doors, clearing emergency stops, or resolving safety system faults before attempting to exit dry run mode.