Set negative software limit switch (G98)

G98                                         Set negative software limit switch                                (non-modal)

G98 sets the negative limit switch positions in [mm, inch] in all programmed axes. Depending on the G90/G91 setting, this may be absolute or additive to the previous software limit switch position.

The positions for negative limit switches are saved in the axis-specific variables:

V.A.-SWE.X,           V.A.-SWE.Y,            V.A.-SWE.Z, etc.

(see also Section Axis-specific variables).




…only applies to the command G98; the software limits switches themselves are effective in modal mode.

After machine start-up, the default value of axis parameter P-AXIS-00177 is valid first.

This limit value can be further restricted in the NC program by programming G98 but cannot be increased. In other words, the limit value defined in the axis parameter list cannot be increased by G98.

In static axis constellations (without axis exchange) the limit value changed in the NC program remains valid at program end and is also effective in the next NC program activated. Only after CNC Reset followed by a program restart, the original default value becomes valid again.

In dynamic axis constellations (with axis exchange) reset to the original default value is executed when the axis is adopted in the channel.

A G98 change acts on the axis motion path range, on independent axes and on single axes. The motion path ranges in manual mode are not affected; they are influenced by the NC command #MANUAL LIMITS [...].

Programing Example


Set negative software limit switch (G98)

N10 G90


N100 G98 X-1000 Y-2000           Sets negative software limit switch

                                 in X to –1000 and in Y to –2000