What causes Siemens SINUMERIK alarm 62305?

Programmed dimension or tool offset is smaller than the lower tolerance limit (_TLL) parameter setting. Tool wear or tool breakage has reduced effective cutting diameter below minimum acceptable size. Incorrect tool selection or tool table entry with undersized geometry. Parameter _TLL value set too high for the intended machining operation. Accumulated part tolerance stack-up causing dimension to fall below acceptable range.

How do I fix Siemens SINUMERIK alarm 62305?

1. Review the active cycle (CYCLE974, CYCLE977, CYCLE978, CYCLE979, or CYCLE994) block and verify programmed dimensions match part drawing specifications 2. Check the lower tolerance limit (_TLL) parameter value and compare against actual part tolerance requirements; adjust parameter downward if specification permits 3. Inspect the active tool for wear, chipping, or breakage; measure actual tool diameter and compare to tool table entry; replace or re-offset tool as needed 4. Verify tool offset values in the tool table are correct and within expected range; re-measure tool on tool presetter if available 5. Run a dry cycle verification or single-block execution to monitor actual versus setpoint values and confirm dimension is achievable with current setup

Siemens SINUMERIK codes

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Siemens SINUMERIK Controller

Servo/Axis · Intermediate · 30-45 minutes

Alarm 62305

Siemens 840D 62305 - Channel Block: Dimension too small

The alarm is triggerd by the following cycles: CYCLE974, CYCLE977, CYCLE978, CYCLE979, CYCLE994 Remedy: The difference between actual and setpoint value is smaller than lower tolerance limit (parameter _TLL).

Siemens SINUMERIKServo/AxisIntermediate30-45 minutes

62305

Siemens 840D 62305 - Channel Block: Dimension too small

Channel Block: Dimension too small

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Common Causes

Programmed dimension or tool offset is smaller than the lower tolerance limit (_TLL) parameter setting
Tool wear or tool breakage has reduced effective cutting diameter below minimum acceptable size
Incorrect tool selection or tool table entry with undersized geometry
Parameter _TLL value set too high for the intended machining operation
Accumulated part tolerance stack-up causing dimension to fall below acceptable range

Troubleshooting Steps

1Review the active cycle (CYCLE974, CYCLE977, CYCLE978, CYCLE979, or CYCLE994) block and verify programmed dimensions match part drawing specifications
2Check the lower tolerance limit (_TLL) parameter value and compare against actual part tolerance requirements; adjust parameter downward if specification permits
3Inspect the active tool for wear, chipping, or breakage; measure actual tool diameter and compare to tool table entry; replace or re-offset tool as needed
4Verify tool offset values in the tool table are correct and within expected range; re-measure tool on tool presetter if available
5Run a dry cycle verification or single-block execution to monitor actual versus setpoint values and confirm dimension is achievable with current setup

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