Siemens SINUMERIK 840C - Manual (Page 835)

12 Functional Descriptions 06.93
12.7.2 Description of the spindle modes
Encoder-specific resolution
Any type of encoder for actual value acquisition (e.g. digital encoders with any pulse rate,
SIPOS signal generators) can be used for spindles controlled by 32-bit servo CPUs.
When SIPOS signal generators are used, employing the pulse multiplication on the HMS
measuring circuit module also allows a higher resolution to be attained.
The internal calculations for the spindle are performed with the value of resolution provided by
the measuring system (the measuring-system resolution). The matching to the different pulse
rates is performed in the same way as with axes by means of variable incremental weighting
(MD 455*, 456*).
When a spindle is assigned to a C axis via MD 461* (for C axis mode or synchronous mode),
the internal calculations for the spindle are also performed with the measuring-system
resolution of the C axis. Therefore, the variable incremental weighting for the axis must also be
entered (MD 364*, 368*, 1800*).
If there is no separate encoder for the C axis mode, the values of the spindle encoder must
also be entered in the axis-specific machine data.
If different encoders are used, please make sure that the spindle and C axis measuring system
are parameterized with the same direction of rotation.
If a value other than zero is entered in MD 461*, the variable incremental
weighting for the axis must also be entered.
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SINUMERIK 840C (IA)