Peripheral Devices - Omron SYSMAC C2000H Operation Manual

Peripheral Devices

Control System Design
Input/Output Requirements
Sequence, Timing, and
Relationships
Unit Requirements
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Peripheral Devices

7. Wire the PC to the controlled system. This step can actually be started
as soon as step 3 has been completed. Refer to the C1000H/C2000H
Installation Guide and to Operation Manuals and System Manuals for
details on individual Units.
8. Test the program in an actual control situation and carry out fine tuning
as required. (Section 4 Writing and Inputting the Program, Section 7
Program Debugging and Execution, and Section 8 Troubleshooting)
9. Record two copies of the finished program on masters and store them
safely in different locations. (Section 7 Program Debugging and Execu-
tion)
Designing the Control System is the first step in automating any process. A
PC can be programmed and operated only after the overall Control System is
fully understood. Designing the Control System requires, first of all, a thor-
ough understanding of the system that is to be controlled. The first step in
designing a Control System is thus determining the requirements of the con-
trolled system.
The first thing that must be assessed is the number of input and output points
that the controlled system will require. This is done by identifying each device
that is to send an input signal to the PC or which is to receive an output sig-
nal from the PC. Keep in mind that the number of I/O points available de-
pends on the configuration of the PC. Refer to 3-2 IR Area for details on I/O
capacity and the allocation of I/O bits to I/O points.
Next, determine the sequence in which control operations are to occur and
the relative timing of the operations. Identify the physical relationships be-
tween the I/O devices as well as the kinds of responses that should occur
between them.
For instance, a photoelectric switch might be functionally tied to a motor by
way of a counter within the PC. When the PC receives an input from a start
switch, it could start the motor. The PC could then stop the motor when the
counter has received a specified number of input signals from the photoelec-
tric switch.
Each of the related tasks must be similarly determined, from the beginning of
the control operation to the end.
The actual Units that will be mounted or connected to PC Racks must be de-
termined according to the requirements of the I/O devices. Actual hardware
specifications, such as voltage and current levels, as well as functional con-
siderations, such as those that require Special I/O Units or Link Systems will
need to be considered. In many cases, Special I/O Units, Intelligent I/O Units,
or Link Systems can greatly reduce the programming burden. Details on
these Units and Link Systems are available in appropriate Operation Manu-
als and System Manuals.
Once the entire Control System has been designed, the task of program-
ming, debugging, and operation as described in the remaining sections of
this manual can begin.
The following peripheral devices can be used in programming, either to input/
debug/monitor the PC program or to interface the PC to external devices to
output the program or memory area data. Model numbers for all devices
listed below are provided in Appendix A Standard Models. OMRON product
Section 1-6
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