Programming; Boundary Conditions - Siemens SINUMERIK 840D sl Function Manual

8.5.11.3

Programming

Transferring the brake to the leading axes
For generic couplings, type "freely programmable" (CPSETTYPE[FAx] = "CP"), by
programming the coupling property CPMBRAKE (see "Reaction to stop signals and commands
(CPMBRAKE) (Page 411)") it can be set as to whether the brake of the following axis, initiated
using the "CP-SW limit monitoring" function, should also be transferred to the leading axes.
8.5.11.4

Boundary conditions

Possible fault sources
If the axes do not brake as required, this could be due to the following reason:
At least one leading axis does not react to the brake, because it is also a leading axis in its
own right (cascade), and the brake is not transferred to its leading axes. A brake is only
transferred to the leading axes (recursive), if the following applies for the following axes
involved: CPSETTYPE[FAx] = "CP" and CPMBRAKE[Fax] bit 0 = 1
Even if all of the axes brake as required, the contour can be violated as a result of different
acceleration rates and/or coupling factors if these values have not been appropriately
configured and/or programmed.
Even if all of the previous preconditions are fulfilled, there are still some reasons why it cannot
be avoided that a following axis passes a software limit switch:
● The actual maximum acceleration of a leading axis changes.
● The actual maximum acceleration of the following axis becomes smaller.
● The velocity of the following axis when switching in the coupling or when the CP-SW limit
monitoring responds is already so high that with the actual
maximum acceleration it is no longer possible to stop the axis in the appropriate time.
If the axis cannot be stopped in the appropriate time, then as before, the previous software
limit switch monitoring responds, and stops the following axis at the software limit switch.
Braking response for transformations
If the axis to be braked is the output of a transformation, and it has a (MCS) travel command
in the collision direction, then the brake is transferred to all input axes of the transformation in
both directions, and a path stop is executed for this transformation. However, the following
exceptions apply: It does not apply to the independent axes of the transformation. For
TRANSMIT and TRAANG, these are the axes specified in machine data
$MC_TRAFO_AXES_IN_*[2]. For the transformations, braking is only transferred to their
dependent input axes.
DRF offset
Setting a CP-SW limit stop can cause a DRF movement to be canceled, as shown in the
following example:
Special functions
Function Manual, 01/2015, 6FC5397-2BP40-5BA2
M3: Coupled axes
8.5 Generic coupling
431