HEIDENHAIN TNC 620 (81760x-02) Cycle programming - Manual (Page 289)

ASCERTAIN THE LOAD (Cycle 239, DIN/ISO: G239, software option
143)
11.8
11
TNC 620 | User's Manual Cycle Programming | 2/2015
289
11.8 ASCERTAIN THE LOAD (Cycle 239,
DIN/ISO: G239, software option 143)
Cycle run
The dynamic behavior of your machine may vary with different
workpiece weights acting on the machine table. A change in the
load has an influence on the friction forces, acceleration, holding
torque and stick-slip friction of table axes. Option 143 LAC (Load
Adaptive Control) and Cycle 239 ASCERTAIN THE LOAD enable
the control to automatically ascertain and adapt the current mass
moment of inertia of the load as well as the current friction forces,
or to reset the feedforward and controller parameters. In this
way, you can optimally react to major load changes. The TNC
performs a weighing procedure to ascertain the weight acting on
the axes. In the weighing procedure, the axes move a specified
distance—the machine tool builder defines the exact scope of axis
movement. Before weighing, the axes are moved to a position, if
required, where there is no danger of collision during the weighing
procedure. This safe position is defined by the machine tool builder.
Parameter Q570 = 0
1 There is no physical movement of the axes.
2 The TNC resets the LAC.
3 The TNC activates feedforward parameters and, if applicable,
controller parameters that ensure a safe movement of the axes
concerned, regardless of the load condition—the parameters
set with Q570=0 are
independent of the current load.
4 These parameters can be useful during the setup procedure or
after the completion of an NC program.
Parameter Q570 = 1
1 The TNC performs a weighing procedure in which it moves one
or more axes. Which axes are moved depends on the setup of
the machine and on the drives of the axes.
2 The scope of axis movement is defined by the machine tool
builder.
3 The feedforward and controller parameters determined by the
TNC depend on the current load.
4 The TNC activates the parameters determined.
Please note while programming:
Cycle 239 becomes effective immediately after
definition.
If you are using the mid-program startup function and
the TNC skips Cycle 239 in the block scan, the TNC
will ignore this cycle—no weighing procedure will be
performed.
The machine must be prepared by the machine tool
builder for this cycle.
Cycle 239 can only be used with option 143 LAC
(Load Adaptive Control).