Omron NX Series Hardware User Manual page 31

shorter than the control period, the MC Function Module may not be able to detect the input signals,
resulting in incorrect operation.
• 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
• Backup function allows to save various setting data in the Controller to an SD Memory Card or a
computer.
If you back up data when the operating mode is set to the RUN mode, the concurrency of variables
with a Retain attribute (i.e., structure and array variables of two bytes or more) may be lost.
To ensure data concurrency, we recommend that you back up data when the operating mode is set
to PROGRAM mode.
NX-series NX102 CPU Unit Hardware User's Manual (W593)
LastOnPosition
FirstOnPosition after compensation
LastOnPosition
OffCompensation
Precautions for Safe Use
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