Rockwell Automation 1785-LTx,D17856.2.1 Classic PLC-5 Programmable Controllers Users Manual User Manual
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Choosing Communication
Chapter 5
5-3
You select scanner or adapter mode for your PLC-5 processor by setting
switches.
Configure Processor Communication
You configure the processor by setting switch assemblies SW1 and SW2
on the processor. See Appendix A for information on switch settings.
Follow these steps to plan configuration for your processor.
1.
Select scanner or adapter mode on switch assembly SW1 (the
PLC-5/10 and -5/12 can not be configured as scanners).
2.
If you select adapter mode, assign a rack address (rack number 0-77
octal) on switch assembly SW2. The supervisory processor uses this
address to reference the adapter-mode processor.
3.
If you select adapter mode, specify the simulated chassis size, either
an 8-slot or 16-slot I/O chassis, and the corresponding first I/O group
on switch assembly SW2. The simulated chassis size and first I/O
group determine the number of discrete-transfer data words (4 words
for an 8-slot chassis, 8 words for a 16-slot chassis) that the processor
transfers to and from the supervisory processor during the
supervisory processor’s remote I/O scan.
Note that the actual size of the chassis has no bearing on the
simulated size of the chassis.
You can use a DH+ link for data transfer to higher level computers and as a
multiple PLC-5 processor programming link. A PLC-5 processor can
communicate over a DH+ link with other processors and with a
programming terminal. You can connect a maximum of 64 stations to a
DH+ link. The network operates under a token-passing protocol with data
transfer at 57.6 kbps.
See your programming software documentation set to configure a
processor for DH+ communication.
Estimating Data Highway Plus Link Performance
Many factors can affect the performance of your DH+ link, including:
nodes
size and number of messages
message
destination
internal processing time
Configuring Communication
for Your Processor
Configuring a DH+ Link