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Siemens SINUMERIK Controller
Program/G-code · Intermediate · 30-120 minutes
Siemens 840D 104202 - Tool identifier not defined
Alarm 104202 occurs when the NC program references a tool using an identifier (name or variable) that does not exist in the active tool management system. The control cannot locate the tool definition in the tool list, magazine, or tool offset tables, preventing execution of the programmed tooling operation.
104202
Siemens 840D 104202 - Tool identifier not defined
Tool identifier not defined
Siemens SINUMERIK operator message 104202: Tool identifier not defined. This is an informational message from the SINUMERIK control indicating a system status or operation result that may require operator action.
Root Cause Summary
Alarm 104202 occurs when the NC program references a tool using an identifier (name or variable) that does not exist in the active tool management system. The control cannot locate the tool definition in the tool list, magazine, or tool offset tables, preventing execution of the programmed tooling operation.
Safety
- Refer to Siemens documentation
- Ensure qualified technician performs repairs
Causes and Fixes
- 1
Identify the exact tool identifier from the alarm detail or NC program line where the alarm occurred.
- 2
Navigate to tool management: Press OFFSET key, select 'Tool List' or access via 'Parameters > Tool Management > Tool Data'.
- 3
Search for the tool identifier in the tool list. If missing, create new tool entry with correct name, assign T-number, and input basic geometry data (length, radius).
Ensure tool names match exactly including case sensitivity and special characters if system is configured for case-sensitive names.
- 4
Reload or restart the NC program. Verify tool is properly loaded with M6 or tool change command executes without alarm.
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