Siemens SINUMERIK 828D Function Manual page 1500

W1: Tool offset
18.6 Toolholder with orientation capability
Limited toolholder orientation
An alarm is output if an orientation that cannot be reached with the defined toolholder kinematic is specified by
the frame.
The following kinematics cannot achieve any orientation:
• If the two rotary axes, which are necessary to define the kinematic, are not perpendicular to each other and if
the tool axis, which defines the tool direction, does not stand perpendicular to the second rotary axis
or
• Fewer than two axes have been defined.
Non-rotary toolholders
The tool orientation used internally is dependent only on the basic orientation of the tool and the active plane
(G17 - G19).
Ambiguities
With two axes, a particular tool orientation defined by the frame can generally be set with two different rotary
angle pairs. Of these two, the control selects the setting with which the rotary angle is as close as possible to the
programmed rotary angle.
Storing angles in the toolholder data
In virtually any case where ambiguities may arise, it is necessary to store the approximate angle expected from
the frame in the toolholder data.
Parameter sets
A complete set of parameters for a toolholder with orientation capability consists of 33 values.
The following system variables are available:
• $TC_CARR1 to $TC_CARR33
• In addition, $TC_CARR34 to $TC_CARR65 are freely available for the user and for fine offsets.
The significance of the individual parameters is distinguished as follows:
Machine kinematics:
$TC_CARR1 to $TC_CARR20 and $TC_CARR23
$TC_CARR18 to $TC_CARR20 define a further vector l
kinematics (both tool and workpiece can be rotated).
$TC_CARR21 and $TC_CARR22 contain the channel-axis identifiers of the rotary axes, the positions of which
can be used to determine the orientation of the toolholder with orientation capability, if necessary.
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which is needed to describe the machine with extended
4,
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Basic Functions