905-2832

Check Tool Number Range

Access MOD function and check machine parameter MP7260 to verify maximum allowed tool number. Compare with the tool number causing the alarm.

Most Heidenhain systems default to 254 or 999 maximum tools depending on configuration

Verify Tool Table Entry

Press TOOL TABLE key and navigate to the problematic tool number. Ensure the tool exists and has valid LENGTH and RADIUS values entered.

Never use tool number 0 in programming - this is reserved for spindle without tool

Check Program Tool Call

Review the NC program at the line causing the alarm. Verify T number in TOOL CALL or M6 command is within valid range and matches tool table entries.

Check Tool Table File Status

Access PGM MGT (Program Management) and navigate to TNC:\table\. Check if TOOL.T file shows any error indicators or unusual file size.

A corrupted TOOL.T file often shows 0 bytes or cannot be opened

Backup and Reset Tool Table

Create backup of current TOOL.T, then access TOOL TABLE and use soft key 'RESET TABLE' to reinitialize. Re-enter critical tool data.

Resetting tool table will erase all tool data - ensure backup exists first

Verify File System Integrity

Perform TNC file system check via MOD function, select 'System Info' and run disk check to identify any file system errors.

Check Spindle Encoder Parameters

Access machine parameters MP3010-MP3019 (spindle encoder settings) and verify correct encoder type and resolution values match the installed hardware.

Common encoder resolutions are 1024, 2048, or 4096 pulses per revolution

Verify Encoder Cable Connections

Inspect X41 connector (typical spindle encoder connection) for loose connections, damaged pins, or cable shield continuity.

Power down machine before checking encoder connections

Test Spindle Position Feedback

Use TNC diagnostic screen (CTRL+DIAG) to monitor spindle position values during manual spindle rotation. Values should change smoothly without jumps.

Check Tool Change Cycle

Access PGM MGT and navigate to TNC:\system\. Open TOOL CALL.cyc file and review tool number parameter handling in the macro logic.

Look for parameter Q operations that might modify or corrupt the tool number variable

Review PLC Tool Change Logic

Access PLC program via MOD function and examine tool change sequence. Check for proper tool number transfer between NC and PLC.

PLC modifications require advanced knowledge - document all changes

Test with Simple Tool Call

Create test program with basic 'TOOL CALL 1 Z' command to isolate if error occurs with standard tool calls or only complex sequences.