Siemens SINUMERIK 840D sl Function Manual page 399

Access protection
Currently there is no protection against access to the compensation tables.
Setting servo enables
As a result of the compensation relationship, a traversing movement by the base axis may
also cause the compensation axis to move, making it necessary for controller enable signals
to be set for these axes (PLC user program). Otherwise the compensation only has a limited
effect.
Traversing signal output
The traversing signals in the compensation axis are output every time the compensation
function is switched on/off and every time the number of active compensation tables
changes.
Any change in the compensation value caused by the base axis motion does not result in
output of traversing signals in the compensation axis.
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Compensations (K3)
Interpolatory compensation
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