The calibration process for the Renishaw FCR25 Probe Changer represents the steps that you would take to prepare to use any of the probe changers that PC-DMIS supports. The process discussed here is specific to the FCR25 Probe Changer.
Two inserts are used with the FCR25 rack to accommodate different probe types: PA25-SH and PA25-20.
PA25-SH and PA25-20 Inserts
For example, the following image of an FCR25 Probe Changer shows three ports: two with inserts and one without (probes are also shown). The left port shows a PA25-SH insert, and the right port shows a PA25-20 insert. The middle port does not have an insert.
FCR25 Probe Changer inserts and probe types
The FCR25 Probe Changer must be mounted on the machine
table parallel to either the X or Y axis for successful calibration. The
FCR25 Probe Changer can be mounted to your table with the MRS rack or
the three and six port stand-alone racks. 
For mounting instructions, consult the documentation that came with your
probe changer.
To calibrate your probe changer:
Step 1 - Select the FCR25 Probe Changer
Step 2 - Define the Mount Point
Step 4 - Prepare the Probe Changer
Step 6 - Measure Port 1 / PA25-SH Insert
Step 7 - Measure Port 3 / PA25-20 Insert
