The Fixturing System is comprised of three different elements: Fixture System, Fixture Definition, and Fixture Instance.
The Fixture System consists of the CMM, and columns and modules of the DCC or Manual fixturing system. The rack systems and the number of columns vary according to the needed configuration. The Fixture System doesn't really concern itself with specific fixtures; instead, it is the components that make up its system.
The Fixture Definition is a file that lists the points in the part coordinates and the requested modules that correspond to those specific points. The fixture definition is machine and system independent so that it can be ported to any machine and any fixture system (manual or DCC). There is no relation with the fixture definition and any machine. The Fixture Definition could be on a central computer that is accessed by several different fixture servers. Deleting the definition from within the fixture server deletes only the definition, and it does not affect the status of the machine.
The Fixture Instance is the specific instance of the Fixture Definition on a given Fixture System. This element only exists in memory long enough to load or unload a given fixture definition. This links the generic Fixture Definition to a specific Fixture System. The Fixture Instance is not saved; it is recreated every time a fixture is executed, either for load or unload. Measurement routine commands only affect the system when they are executed.
Editing your measurement routine does not affect the status of a machine unless you specifically cause changes to be made. For example, if you delete a LOADFIXTURE command from the measurement routine, the status of the machine is not affected. However, if you want to physically remove the fixture from the plate of the machine and delete it from the measurement routine, then you must first execute the same LOADFIXTURE command with the UNLOAD flag and then delete the LOADFIXTURE command from the measurement routine.