PLC-5 System

Catalogs > Automation Systems Catalog > Programmable Controllers > PLC-5 System > PLC-5 Processors

PLC-5 Processors

PLC-5 Processors Overview Specifications Selecting the Processor Category PLC-5 Processors PLC-5 Processor Backup System
PLC-5 Processors Overview

Click to enlarge - 1771Chassis_ProcMods_4C

The PLC-5® processors are single-slot modules that are placed into the left-most slot of a 1771 I/O chassis. They are available in a range of I/O, memory, and communication capability.

PLC-5 processors have ports configurable for either a Data Highway Plus messaging communication link or a Universal Remote I/O link. As a Universal Remote I/O port, it can be configured as either an I/O scanner port or an I/O adapter port. As an I/O scanner port, it monitors and controls the I/O on the link by communicating with the I/O adapters for those I/O. As an adapter port, it communicates only with the I/O scanner port on the link, passing a maximum of one I/O rack of input and output data between the two to provide distributed processing.

All PLC-5 processors have Data Highway Plus and RS-232-C/422-A/423-A communication ports. In addition to these ports, each Ethernet PLC-5 processor has an Ethernet communication port, and each ControlNet PLC-5 processor has a ControlNet communication port.

Although each Ethernet PLC-5 processor has on-board Ethernet ports; additional Ethernet ports can be added to any PLC-5 processor system with a 1785-ENET Ethernet Interface Module. PLC-5 processors do not have an on-board DeviceNet port. A DeviceNet port can be added to the system with a 1771-SDN scanner module.


Built-in Web Services

Ethernet PLC-5 processors (1785-L20E, -L40E, and -L80E), and the Ethernet interface module (1785-ENET) provide built-in web capabilities:

PLC-5 Processors with Protected Memory (1785-L26B, -L46B, L86B, -L46C15)

All enhanced PLC-5 processors have memory protection. However, those processors designated as having the memory protection feature have the added capability of limiting access to individual words.

Choose a PLC-5 processor with protected memory when access must be limited to critical or proprietary areas of programs, selectively guard processor memory and I/O words, or restrict use of processor operations.

The PLC-5 protected memory feature expands system validity and security beyond what is provided by the password-and-privilege capability of the other PLC-5 enhanced processors. Custom software protection schemes can be designed for each application.

Rockwell Software programming software can be used to assign class privileges to specific user accounts or a user job function, such as system administrator, plant engineer, maintenance engineer, or operator. Using four privilege classes and associated passwords, access can be limited to critical program areas and restrict access to:

The PLC-5/26, PLC-5/46, and PLC-5/86 protected processors are equivalent to the PLC-5/20, PLC-5/40, and PLC-5/80 standard processors, respectively, plus the added memory protection feature. These processors are listed under the heading "Standard PLC-5 Processors with Protected Memories" in the PLC-5 Processor selection tables.

The PLC-5/46C15 protected processor is equivalent to the PLC-5/40C15 ControlNet processor plus the added memory protection feature. This processor is listed under the heading "ControlNet PLC-5 Processors with Protected Memories" in the PLC-5 Processor selection tables.