Siemens SINUMERIK 840D sl Function Manual page 559

7.5.3 Special characteristics of chained transformations
Tool data
A tool is always assigned to the first transformation in a chain. The subsequent
transformation then behaves as if the active tool length were zero. Only the basic tool
lengths set in the machine data (_BASE_TOOL_) are valid for the first transformation in the
chain.
Example
The chapter "Chained transformations" contains configuration examples for single
transformations and the transformation chains created from them.
See also
Chained transformations (Page 556)
7.5.4 Persistent transformation
Function
A persistent transformation is always active and has a relative effect to the other explicitly
selected transformations. Other selected transformation are computed as the first chained
transformation in relation to the persistent transformation.
Transformations such as TRANSMIT that must be selected in relation to the persistent
transformation must be parameterized in a chain with the persistent transformation by means
of TRACON. It is the first chained transformation rather than the TRACON transformation
which is programmed in the part program.
For additional programming tips see
References:
/PGA/ Programming Manual Work Preparation; Transformations "Chained Transformation"
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Kinematic Transformation (M1)
Chained transformations
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