Omron NX Series Hardware User Manual page 31

• If you make any changes in the Detailed Settings Area of the Axis Basic Settings Display of the
Sysmac Studio, make sure that the devices or machines perform the expected operation before you
start actual operation.
If the relationship between the functions of the Motion Control Function Module and the EtherCAT
slave process data that is assigned to the axes is not correct, the devices or machines may perform
unexpected operation.
• Always use the axis at a constant velocity for the MC_DigitalCamSwitch (Enable Digital Cam
Switch) instruction.
If you set the Count Mode to Rotary Mode, the following operation will occur if you use OnCompen-
sation or OffCompensation and the axis velocity changes abruptly.
a) If the value of OnCompensation or OffCompensation is equivalent to the time for half a rotation
or more, InOperation will be FALSE.
b) If the value of OnCompensation results in exceeding LastOnPosition, the output timing will be
unstable.
FirstOnPosition
OnCompensation
c) If the value of OffCompensation results in exceeding FirstOnPosition, the output timing will be
unstable.
FirstOnPosition
LastOnPosition after compensation
• Use the NX_AryDOutTimeStamp (Write Digital Output Array with Specified Time Stamp) instruction
only after you confirm that InOperation from the MC_DigitalCamSwitch (Enable Digital Cam Switch)
instruction is TRUE.
• If you change the unit conversion settings, perform homing again. If you do not perform homing, un-
intended operation of the controlled system may occur.
Backing Up Data
• We recommend that you back up the present values of variables while the retained variables are not
refreshed.
If you back up variables while the values of retained variables are refreshed, the data may not be
saved correctly.
Refer to the NJ/NX-series CPU Unit Software User's Manual (Cat. No. W501) for details on the
backup function and backing up the present values of variables.
NX-series NX502 CPU Unit Hardware User's Manual (W629)
LastOnPosition
FirstOnPosition after compensation
LastOnPosition
OffCompensation
Precautions for Safe Use
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