CNC Motion Setup/Testing Utility
P/N 70000510B
All rights reserved. Subject to change without notice.
25
31-January-05
1. Line 1 of the graph area indicates the number of active CanBus I/O
nodes and their status.
2. Line 2 of the graph area indicates the state of the touch probe input
when a probe is connected to the Motion Control Board (MCB):
0
Not deflected (touching)
1 Deflected
(touching)
3. Line 3 of the graph area indicates the basic machine I/O status.
4. Line 4 of the graph area indicates:
The address of the active node. Possible values are 0 to 5.
The number of message packets lost between the node and the
controller. This should be 0.
The number of times the node has signed on since the control
started. This should be 1 unless power was interrupted.
The node bus type. This is normally 0.
5. Line 5 indicates:
The status of the ten inputs of each node.
The status of the six outputs of each node.
6. Subsequent lines indicate the I/O status of any additional nodes.
Rigid Tapping Test
This test displays the lag between the spindle and the Z-axis velocity as a
measurement of synchronization between the mentioned axes. The
display units are microns per position loop sample. After the test is
selected, a G84 command has to be issued through Manual Data Input
(MDI). There is also the possibility to run a G program in MDI containing
the G84 command by calling it with quotes. For example: typing
“RTAP.G” in the MDI line will run program RTAP.G. In general, a
program ran in this manner should be small (that is, less than 15 lines).
The lag display has 3 main sections:
a) Going in
b) Reversing direction (retract)
c) Going out the thread
If the controller is optimally tuned, the sections [a] and [c] should present
near zero lag. Any peak on these sections means that either the spindle
or Z-axis motors are not reaching their final speeds. The most critical
section is [b] since some lag will appear when reversing direction. This
lag will increase proportionally to the spindle rpm and it may be
diminished by fine-tuning the rigid tapping gains of the Proportional
Integral Derivative (PID) controller in the Z-axis (proportional gain [Kp]
and feedforward gain [Kf]). As a point of reference, the threading
(sections [a] and [c]), the retract lag (section [b]), and the Z-axis lag are
displayed on the screen after each rigid tapping cycle. Also, gains Kp
and Kf for the Z-axis can also be changed in the test before the cycle is
commanded.
