With the BLOCK SCAN function you can start an NC program at any desired NC block. The control will arithmetically account for workpiece machining up to this NC block. For example, the control will switch on the spindle before the start.
Application
Related topics
- Creating NC programs
- Pallet tables and job lists
Pallet Machining and Job Lists
Requirement
- The function must be enabled by your machine manufacturer.
The Block scan function must be enabled and configured by your machine manufacturer.
Description of function
- If the NC program was interrupted under the following conditions, the control saves the interruption point:
- Internal stop button
- Emergency stop
- Power failure
If, while restarting, the control finds a saved point of interruption, then it outputs a message. You can then execute a block scan directly to the point of interruption. The control displays the message when you switch to Program Run operating mode for the first time.
- You have the following options for a block scan:
- Block scan in the main program, with repetitions if necessary
- Multi-level block scan in subprograms and touch probe cycles
- Block scan in a point table
- Block scan in pallet programs
Performing a single-level block scan
Performing a multi-level block scan
At the start of the block scan, the control resets the data, as with a selection of a new NC program. During a block scan you can activate or deactivate Single Block mode.
Block scan window

The Block scan window provides the following data:
Row | Meaning |
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Pallet number | Row number in the pallet table |
Program | Path of the active NC program |
Block number | Number of the NC block at which program run should start Use the search icon to select the NC block in the NC program. |
Repetitions | Number of the repetition for mid-program startup if the desired NC block is located within a program-section repeat. |
Last pallet number | Pallet number that is active at the time of interruption Select the interruption point by using the Select last button. |
Last program | Path of the NC program that is active at the time of interruption Select the interruption point by using the Select last button. |
Last block | Number of the NC block that was active at the time of interruption Select the interruption point by using the Select last button. |
Point file | Path of the point table In the Point table area |
Point number | Row in the point table In the Point table area |
Performing a single-level block scan
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Tip You can also position the axes individually in a self-selected sequence. | ||
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Performing a multi-level block scan
If you, for example, start in a subprogram that is called several times by the main program, then use the multi-level block scan. For this, you first go to the desired subprogram call and then continue the block scan. The same procedure is used for called NC programs.
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Tip You can also position the axes individually in a self-selected sequence. | ||
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Block scan in point tables
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Tip You can also position the axes individually in a self-selected sequence. |
If you would like to use the block scan function to start in a point pattern, then use the same procedure. Define the desired point for mid-program startup in the Point number field. The first point in the point pattern has the number 0.
Block scan in pallet tables
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Tip You can also position the axes individually in a self-selected sequence. |
If the program run of a pallet table has been canceled, the control will suggest the most recently selected NC block of the most recently executed NC program as a point of interruption.
Notes
- Use GOTO only when programming and testing NC programs
- Only use Block scan when executing NC programs
- Use the Block scan function at multiple levels
- The control only displays the dialogs required by the process in the pop-up window.
- A Block scan always takes place in a workpiece-oriented manner, even if you selected a tool-oriented machining method. After the block scan, the control continues working again in accordance with the selected machining method.
- Even after an internal stop, the control shows the number of repetitions on the LBL tab of the Status workspace.
- The Block scan function must not be used in conjunction with the following functions:
- Touch probe cycles 0, 1, 3, and 4 during the block scan search phase
- HEIDENHAIN recommends switching the spindle on with M3 or M4 after every tool call. That way you avoid problems during program run, such as when restarting after an interruption.