OmniTurn Technical Note

Problem:  Repeatability of an axis.  An axis has a small accumulating error.  The operator has to constantly correct the offsets

Corrective action: Ctrl-C / Ctrl-H tests

  • These two tests will determine if the problem is in the control or the axis motor without needing any additional tooling or indicators

Note: before starting this check to see that all connections on the MC-2 and servo cables are clean and have no obvious defects! Checks to see all pins on the axis cables are level and not pushed back!

Procedure

  • Home the slide twice to clear the registers. (in jog mode press 9 and then cycle start)

  •  

    Run the following program.  Be sure the program will not cause any of your tools to be damaged.  It is important that the program be run from the Home location.  Notice that there are no tool calls.

G90G94F300

X1

Z-1

G02X1Z0i1K-.5

G03X1Z-1i1K-.5

X0Z0

M30
  • Use cycle repeat and run this program 100 times

  • Go to the jog mode

  • Tell the slide to go home, do not re-home the slide.

Press CTRL and C.  The counters displayed should read Zero.  If not, then there is a problem with the MC2 motion control card.  Have it replaced or repaired by the factory.  If the counters are Zero, go to the next step

Re-establish home. From the jog page, use # 7 (.1") to Jog the slide from it's home Position, press 9, Cycle start.

Press CTRL and H.  The counters should show Zeros.  If they don't, there is either a problem with the MC-2 card or one of the axis motors. To determine this, write down the numbers you got for "X" and "Z" and press ESC. Now press the "E" STOP on the control. Switch the "X" and "Z" cables at the back of the control. Release the "E" STOP and turn on the servos. Now re-home the machine twice to clear the registers, keeping in mind that when you move "X" on the jog stick, you will be moving the "Z" axis and visa versa. Now write a program of liner moves keeping this in mind and run it at least 10 times. If the axis that read other than zero still reads other than zero, than the problem is in the control (MC-2). If it changes to the other axis, then the problem is in that motor (The problem followed the motor). Replace the defective part and place back in service.

Note: If both axes read zero after the control "H" test, then you have a mechanical problem.