NCT Group 2000M, 99M manual Measurement Functions, Skip Function G31

18 Measurement Functions

18 Measurement Functions

18.1 Skip Function (G31)

Instruction

G31 v (F) (P)

starts linear interpolation to the point of v coordinate. The motion is carried on until an external skip signal (e.g. that of a touch-probe) arrives or the control reaches the end-point position specified at the coordinates of v. The control will slow down and come to a halt after the skip signal has arrived. Address P specifies which skip signal input is to be used during movement of the 4 ones available in control:

P0: uses skip signal 1

P1: uses skip signal 2

P2: uses skip signal 3

P3: uses skip signal 4

If address P is not specified, control takes skip signal 1.

G31 is a non-modal instruction applicable only in the particular block, in which it has been programmed. The control returns error message 3051 G22, G28, ... G31, G37 if a syntactic error is found in instruction G31.

The speed of motion is

–the specified or modal value F if parameter SKIPF=0

–the feed value taken from G31FD if parameter SKIPF=1.

In the instant the external signal arrives, the positions of axes will be stored in the system variables specified below.

#5061.........position of axis 1

#5062.........position of axis 2

.

.

#5068.........position of axis 8

Fig. 18.1-1

The position stored there is

–the position assumed in the instant the external signal (if any) has arrived,

–the programmed end-point position of interpolation G31 (unless an external signal has arrived),

–to be understood invariably in the current work coordinate system,

–with the actual length compensation (G43, G44) and

–with the actual tool offset (G45 ... G48) taken into account.

The motion comes to a halt with linear deceleration after the external signal has arrived. Now the end-point position of interpolation G31 is slightly different from the positions stored in variables #5061... on arrival of the signal, the difference varies with the feed applied in the interpolation. The end-point positions of the interpolations are accessible in variables #5001... . The next interpolation will be effective from those end-point positions on.

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