Leaflet: Probe open alarm: information for users of Fanuc controllers (pdf)

The 92(Probe Open) alarm occurs in Renishaw macro software when the probe stylus is already in contact with a surface at a time when a probing move is intended. (It may also occur if the probe is not active.) As machine tool performance increases, Renishaw amends default values within the setting macros of our products. In particular, the ‘back off factor’ (#506) is changed to speed up probing. In some cases this change may increase the likelihood of a probe open alarm occurring on large or older machines which are less able to stop quickly after the stylus first contacts the surface.