19 Safety Functions
19.3 Stroke Check Before Movement
The control differentiates two forbidden areas. The first is the parametric overtravel area which delimits the physically possible movement range of the machine. The extreme positions of that range are referred to as limit positions. During movements the control will not allow those axes to move beyond the limits of that area defined by parameters. The limit positions are set by the builder of the machine; The user may not alter those parameters.
The second is the area defined by the programmable stroke check function. This may be accomplished by programming command G22 or rewriting the parameters.
During any motion the control will not allow the axes to move beyond the limits of these areas. If parameter
CHBFMOVE is set to 1, the control will - before starting the axes
in the course of executing a block - check whether the programmed end point
of the particular interpolation is in a prohibited area.
If the end point of the block is located
outside of the parametric overtravel area or in the programmed forbidden area, error message 3056 LIMIT or 3057 FORBIDDEN AREA will be returned, respectively. As a result, the movement is practically not started at all.
Since, prior to starting
the interpolation, the control only checks
whether the end point of the interpolation is located in a prohibited
area the error message is produced in the
instances shown in the figures at the border of the forbidden area, after the movement has been started.
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