Probe initialisation (home routine)

The SP80 and SP80H utilise digital scale and readhead technology and requires the scale system to be referenced prior to usage following power being supplied to the probe.

The procedure for this is to remove the SH80 stylus holder from the SP80 /SP80H probe body and permit the probe mechanism to return to its zero reference position; when the probe is in this position the scales within the head should be referenced (set to 0). This ‘null' position should be recorded.

When each SH80 is attached, complete with stylus cluster, the offset from the ‘null' position should be recorded and stored for that particular arrangement. This should be recalled every time the stylus holder is reattached.

The difference in position at rest from the offset can be attributed to the return to zero property of the probe. Note that the accuracy of the ‘home' position will be +/- 10 μm. This will lead to a discrepancy between styli calibrated in previous sessions to this one. Hence the OEM should incorporate a more sophisticated homing routine including the location of a known feature.