Resetting HEIDENHAIN Cycle 247 with Preset Row 0 Guide

The panel keeps showing coordinates referenced to the preset selected by Cycle 247. Return to the manually established reference by calling preset-table row 0 with Q339=0. Put that call at the point in the NC program where the original reference must become active; do not expect the end-of-program command to cancel the preset automatically. In manual operation, use the reference-point initialization softkey to redefine row 0 when the stored manual origin itself is wrong.

Read the symptoms first

Start here. Separate an active Cycle 247 preset from a bad machine reference or an incorrect offset file. The coordinate display tells you that a different work reference is active, but it does not prove which table created it.

Symptom or observation	Likely cause or next check
Coordinates remain referenced to a Cycle 247 location	A nonzero preset row is still selected. Call row 0 with Q339=0.
Row 4 contains X, Y, and Z values of zero	Those zeros describe row 4; they do not make row 4 the manually established reference. Check row 0.
You are viewing decalage.d	That is the wrong file for Cycle 247. It is used by Cycle 7, not Cycle 247.
Row 0 does not return the expected coordinates	The manual origin stored in row 0 is wrong or has been reinitialized. Re-establish it in manual mode.
No preset table can be found	Check for preset.pr at the root of the TNC partition. If it does not exist, create it there.

Do not start by editing every zero-valued row. A preset row with zero entries can still represent a different selected reference because the row number, not the appearance of its axis fields, determines which stored preset Cycle 247 calls.

Understand what Cycle 247 changes

Cycle 247 selects an entry from the preset table. The selection is supplied through Q339. Selecting row 4 with Q339=4 activates row 4; selecting row 0 with Q339=0 returns control to the row reserved for origins established manually.

That operation is better treated as a reference selection than as a cycle cancellation. You replace the currently selected preset with another preset. This distinction matters because deleting the Cycle 247 line, ending the program, or changing an unrelated displacement file does not explicitly select the reference you want.

Row 0 has a specific role: it contains the origins established through manual reference-point initialization. Using the panel softkey for that operation modifies row 0. Other preset rows are operator-editable entries used for intentionally stored work references.

Restore row 0 from the program

Place the reset at a controlled point after all motion that depends on the temporary preset. The supported selection value is:

Q339=0

Use that value in the Cycle 247 call or definition format already used by the machine control. The supplied information identifies the parameter and value, but not the complete conversational line syntax. Copy the existing Cycle 247 block format on the control and change only the preset selection to Q339=0.

1. Stop automatic execution at a safe, known program position.
2. Find the Cycle 247 block that selects the working preset.
3. Add a later Cycle 247 call using Q339=0, after the final move that requires the temporary reference.
4. Run the block under normal prove-out controls and watch the displayed coordinates change to the row-0 reference.
5. Confirm that every following position is programmed in the restored coordinate system before continuing automatic motion.

Place this call near the end of the program only when all subsequent blocks are intended to use row 0. If a tool retract, parking move, or subprogram return still uses the temporary preset, switching earlier changes the physical destination of that move.

Restore the origin in manual mode

Use manual mode when row 0 itself no longer represents the required origin. Calling Q339=0 cannot repair incorrect values stored in row 0; it only selects them.

1. Move or probe to the physical reference used for the manual origin according to the machine's established setup method.
2. Open the manual reference-point function.
3. Use the init point de ref softkey to initialize the required axes.
4. Check row 0 in the preset table. The manual initialization updates that row.
5. Call Q339=0 and compare the displayed position with the known physical reference.

Do not reinitialize row 0 merely because row 4 shows zeros. First select row 0 and check its result. Manual reinitialization changes the stored origin and can move every later coordinate based on that row.

Find or create the correct table

Cycle 247 reads a preset table, not decalage.d. Editing decalage.d wastes time because that file belongs to Cycle 7. A correct value in the wrong file cannot change the preset selected through Q339.

1. Open the TNC file manager.
2. Go to the root of the TNC partition.
3. Look for preset.pr.
4. If the file is absent, create preset.pr at that root location.
5. Open the preset table and inspect row 0 before selecting or editing any other row.

Preserve the existing table contents when the file already exists. Creating a second file under another directory or another name does not address the table expected by this setup.

Verify the change and avoid repeat faults

Verify at the coordinate display before commanding production motion. Select row 0, return to a known physical location under controlled movement, and compare the displayed X, Y, and Z positions with the expected row-0 reference. Then single-block the first move that uses the restored system.

• Check the active preset row, not just whether its axis cells contain zeros.
• Keep Cycle 247 work in preset.pr; keep Cycle 7 displacement work separate.
• Do not rely on the program end to restore a coordinate system.
• Do not edit row 0 until a physical reference check proves that row 0 is wrong.
• Do not change to row 0 before completing moves programmed from the temporary preset.
• After manual initialization, verify all affected axes because the softkey operation modifies row 0.

FAQ

Stop and escalate to official HEIDENHAIN or machine-tool-builder support if preset.pr cannot be created or opened, Cycle 247 does not select the requested row, or row 0 changes unexpectedly. Provide the control identification, the Cycle 247 block, the preset-table contents, and the displayed coordinates at a known physical position.