Renishaw RCU10, Installation And User Manual, Page: 19 / 202

1-8 System overview
1.4 Operational functions
A number of useful operational functions (some optional) are available on the RCU10 to
provide flexibility and ease of use.
1.4.1 Selectable parameter tables
A number of ‘parameter tables’ are available for use during operation, which are
selectable through external I/O. These allow easy ‘switching’ of a number of common
options/operations, including:

Dead path or reference offset from scale expansion origin

Workpiece temperature sensor

Workpiece expansion coefficient

Workpiece origin offset

Workpiece origin type
The use of these switchable parameters allows numerous functions such as:

Multiple machine home positions

Changing to an alternative machining zone

Use of multiple workpiece material sensors (for multiple machine zones or other
reasons)

Changing of the material type (e.g. aluminium/steel)
1.4.2 Compensation buffering
When the RCU10 is in this mode, it will continue to monitor the encoder input and perform
the relevant quadrature scaling. However, any injection required to maintain compensated
position will be stored in a buffer within the RCU10. When the mode is disabled, any
stored (buffered) count is slowly injected into the motion feedback loop and the fully
compensated position re-established. The rate at which this compensation is injected is
user-configurable.
This function is useful where an axis needs to be temporarily disabled, but the original
position recovered at a later time. For example, some machines have an Emergency Stop
button that can be used to temporarily stop machine operation, but continue after it is
released without having to re-home the machine. In this case the injection compensation
is buffered, preventing any movement during the ‘E-stop’ period which would cause a
following error on the machine controller.