Omron NJ501-1300, User Manual

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Appendices
NJ-series CPU Unit Motion Control User’s Manual (W507)
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A-3-1 NJ-ser
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A-3 Terminology
This appendix provides definitions of terms related to motion control.
A-3-1 NJ-series Controller
Term Description
main memory The memory inside the CPU Unit that is used by the CPU Unit to execute the OS
and user program.
periodic task Tasks for which user program execution and I/O refreshing are performed each
period.
primary periodic task The task with the highest priority.
period of tasks The interval at which the primary periodic task or a periodic task is executed.
I/O Refresh Cyclic data exchange with external devices that is performed with predetermined
memory addresses.
program One of three POUs. The others are functions and function blocks. Programs are
assigned to tasks to execute them.
user program All of the programs in one project.
Inline ST ST programming that is included within a ladder diagram program.
system-defined variables A variable for which all attributes are defined by the system and cannot be
changed by the user.
global variable Reading and writing global variables are possible from all POUs (programs,
functions, and function blocks).
local variable A variable that can be accessed only from the POU in which it is defined. Local
variables include internal variables, input variables, output variables, in-out vari-
ables, and external variables.
download To transfer data from the Sysmac Studio to the Controller, e.g., with the synchro-
nization operation of the Sysmac Studio.
upload To transfer data from the Controller to the Sysmac Studio, e.g., with the synchro-
nization operation of the Sysmac Studio.
major fault level Control error An error for which all control operations from the NJ-series Controller are not
possible. The CPU Unit stops user program execution immediately and turns
OFF the loads for all slaves and Units (including remote I/O).
partial fault level Controller error An error for which all control operations for one of the function modules in the
NJ-series Controller are stopped. The NJ-series CPU Unit continues operation
even after a partial fault level Controller error occurs.
minor fault level Controller error An error for which some of the control operations for one of the function modules
in the NJ-series Controller are stopped. The NJ-series CPU Unit continues oper-
ation even after a minor fault level Controller error occurs.
observation One of the event levels for Controller information and user-defined information.
Observations represent minor errors that do not affect operation. They are
recorded in an event log to inform the use.