Overview of error reaction classes

Each CNC error message is assigned to an error response class. This error response describes the internal, prompt reaction of the CNC to the error and initiates minimal measures to achieve a safe state from the CNC's point of view.

Error reaction class

internal error reaction

Example(s)

1

No reaction

Only possible in the event of a warning (error class 1)

Programmed feed rate not reached (BAVO).

2

NC program execution aborted and transition to error state

If an error occurs in the NC block preparation area, the interpolator executes the NC blocks that have already been prepared. In this case, the time between the occurrence of the error and machine standstill depends on the type and number of buffered NC blocks. The BF reporting the error assumes an error state.

Syntax error in the NC program (DECODER)

Geometry error in block processing (TRC)

Software limit switch error in block processing (BAVO)

3

Job execution aborted and transition to normal state

After an error message, BFs that provide services for other BFs (servers), for example AXIS ADMINISTRATION, FILE ADMINISTRATION, MANUAL MODE, etc., abort job execution and return to normal state.

Invalid axis requested in the case of BF AXIS ADMINISTRATION

Unknown handwheel activated in MANUAL MODE.

4

Motion stopped (feedhold) for the entire axis group and transition to error state.

Measure:
Probe already actuated.

5

Abrupt axis stop for defective axis, feedhold for the other axes in the axis group and transition to an error state

Due to the position lag of an axis, the interpolator reacts with an axis stop for the axes in its axis group (PATH AXES).

6

Abrupt axis stop for all axes and transition to an error state

Position control assumes an error state.

Unknown state in the
INTERPOLATOR or
POSITION CONTROLLER

7

Closed–loop controlled axis stop for defective axis, feedhold for the other axes in the axis group and transition to an error state

Crossing software limit switches in the POSITION CONTROLLER

8

Open–loop controlled axis stop for defective axis, feedhold for the other axes in the axis group and transition to an error state

The position control loop of the defective axis is opened.

Exceeding the maximum permissible position lag during axis motion in the POSITION CONTROLLER