beautypg.com

Rockwell Automation 8520-GUM 9/Series CNC Grinder Operation and Programming Manual Documentation Set User Manual

Page 217

background image

Running a Program

Chapter 7

7-29

In Figure 7.6, notice that the control only recognized 6 jog moves upon
returning instead of the actual 11 moves that were made to retract the
wheel. This is because the jog retract feature records consecutive jog
moves on the same axis as one move.

ATTENTION: If the number of jog retract moves performed
exceeds the maximum allowed number set in AMP, the control
moves the grinding wheel directly from the final point of jog
retract to the last remembered jog retract point along a straight
line when you press

. Then the wheel is

returned in the normal jog retract fashion.

Figure 7.7

Jog Retract Moves that Exceed the Maximum Allowed in AMP

1

2

3

4

5

6

7

Return path

12011-I

Figure 7.7 emphasizes the possible problems that can result from
exceeding the maximum allowed jog retract moves. In this example, the
number of allowed moves set in AMP is 4.

When you press the cycle start button at the end of the 7th jog move, the
control ignores moves 5, 6, and 7 and takes the shortest path to the
endpoint of exit move 4. This is because the maximum number of jog
retract moves set in AMP has been exceeded. After reaching the endpoint
of move 4, the control continues the jog retract return operation as normal.

If the jogging moves of 5, 6, and 7 were intended to avoid a protrusion
during the jog retract, a collision could result when returning the wheel.