PLC-5 : A 1980s workhorse

As a stunning successor to the PLC3, the PLC5 was launched in 1986 and provided a significant jump in memory and functionality through an expanded instruction set, while retaining use of the rock-solid 1771 IO. Many current programmers and managers learnt their coding on this machine.

PLC5 Chassis

Historically, it was one of the first platforms that could be programmed by a personal computer, with initially the software (A.I) written by Icon, a third party developer, independent of Allen-Bradley. A-B then brought out their own, inferior programming product, 6200, but provided a whole-of-site licence with the purchase, aiming to put A.I out of business. Eventually, Rockwell Automation bought A-B, and Icon as well.

PLC-5 Conversion to ControlLogix

Discontinued from June 2017, supplies will eventually run out, though there are still spares available on eBay, As the price has increased, and they reach 20 or even 30 years in service, migration to ControlLogix is the standard approach to avoiding failure risk.

Pyramid Integrator

The Pyramid Integrator (PLC-5/250) was the most sophisticated model in the family, allowing multiple (up to 4) CPUs in a PI chassis. The PLC-5/250 processor stores and executes compiled instruction code, which executes faster than interpreted code.  Input data can come from other Pyramid Integrator modules in the local chassis and from devices connected to the RM or KA via a DH or DH+ link.

You can have up to four LP modules in one Pyramid Integrator chassis. Each LP executes its own ladder-logic program. The LP has memory for storing ladder-logic programs and data tables. The PLC-5/250 processor stores and executes compiled instruction code, which executes faster than interpreted code.

PI Software

The PI used model 6200 software, for which there were two versions; an online only package, and an online/offline package. (6201-PLC5 vs 6203-PLC5). There were versions for both DOS and VMS. The VMS version had only one version online/offline.

CatalogSeriesDescriptionBattery
1785-LTBPLC-5/15 Processor Module
6kB Memory
1770-XY
1785-LT2APLC-5/25 Processor Module
13kB Memory
1770-XY
1785-LT3APLC-5/12 Processor Module
6kB Memory
1770-XY
1785-LT4APLC-5/10 Processor Module
6kB Memory
1770-XY
1785-LTRBModified PLC-5/15 Processor Module
6kB Memory
1770-XY
1785-LTR2AModified PLC-5/25 Processor Module
13kB Memory
1770-XY
1785-LTR3AModified PLC-5/12 Processor Module
6kB Memory
1770-XY
1785-LTR4AModified PLC-5/10 Processor Module
6kB Memory
1770-XY
5130-RM1APyramid Integrator
128kB Resource Manager Module
1770-XY
5130-RM2Pyramid Integrator
384kB Resource Manager Module
1770-XY
5150-RS2APyramid Integrator
Remote Scanner Module
1770-XY
5150-RS5A5/250 Remote/Local Scanner1770-XY
5250-LP1A, BPyramid Integrator Logic Processor Module1770-XY
5250-LP2A, BPyramid Integrator Processor Module1770-XY
5250-LP3A, BPyramid Integrator Logic Processor Module
1Mb Memory
1770-XY
5250-LP4A, BPyramid Integrator Logic Processor Module
2Mb Memory
1770-XY
1771-DMCAControl Coprocessor
Main Module
256K
1770-XYC/A
1771-DMC1AControl Coprocessor
Main Module
1Mb Memory with EtherNet
1770-XYC/A
1771-DMC4AControl Coprocessor
Main Module
4Mb Memory with EtherNet
1770-XYC/A
1785-L11BA, C, D, EPLC-5/11 Controller
8kB Word SRAM
1770-XYC/A
1785-L20BA, C, D, EPLC-5/20 Controller
16kB Word SRAM
1770-XYC/A
1785-L20BKC, DPLC-5/20 Controller
16kB Word SRAM
Conformal Coated
1770-XYC/A
1785-L30BA, C, D, EPLC-5/30 Controller
32kB Word SRAM
1770-XYC/A
1785-L40BA, B, C, D, EPLC-5/40 Controller
48kB Word SRAM
1770-XYC/A
1785-L40BKC, DPLC-5/40 Controller
48kB Word SRAM
Conformal Coated
1770-XYC/A
1785-L40LA, B, C, D, EExtended Local PLC-5/40 Controller
48kB Word SRAM
1770-XYC/A
1785-L60BA, B, C, D, EPLC-5/60 Controller
64kB Word SRAM
1770-XYC/A
1785-L60LA, B, C, D, EExtended Local PLC-5/60 Controller
64kB Word SRAM
1770-XYC/A
1785-L80BC, D, EPLC-5/80 Controller
100kB Word SRAM
1770-XYC/A
1785-L80BKC, DPLC-5/80 Controller
100kB Word SRAM
Conformal Coated
1770-XYC/A
1785-L16BA, CProtected PLC-5/11 Controller
8kB Word SRAM
1770-XYC/A
1785-L26BA, C, D, EProtected PLC-5/20 Controller
16kB Word SRAM
1770-XYC/A
1785-L36BA, CProtected PLC-5/30 Controller
32kB Word SRAM
1770-XYC/A
1785-L46BB, C, D, EProtected PLC-5/40 Controller
48kB Word SRAM
1770-XYC/A
1785-L46LB, C, D, EProtected Extended Local PLC-5/40
48kB Word SRAM
1770-XYC/A
1785-L66BB, CProtected PLC-5/60 Controller
64kB Word SRAM
1770-XYC/A
1785-L66LB, CProtected Extended Local PLC-5/60
64kB Word SRAM
1770-XYC/A
1785-L86BC, D, EProtected PLC-5/80 Controller
100kB Word SRAM
1770-XYC/A
1785-L20EC, D, EEtherNet PLC-5/20 Controller
16kB Word SRAM
1770-XYC/A
1785-L40EC, D, EEtherNet PLC-5/40 Controller
48kB Word SRAM
1770-XYC/A
1785-L80EC, D, EEtherNet PLC-5/80 Controller
100kB Word SRAM
1770-XYC/A
1785-L20CC, D, EPLC-5/20C for ControlNet Phase 1.251770-XYC/A
1785-L40CC, D, EPLC-5/40C for ControlNet Phase 1.251770-XYC/A
1785-L60CDPLC-5/60C for ControlNet Phase 1.251770-XYC/A
1785-L80CD, EPLC-5/80C for ControlNet Phase 1.251770-XYC/A
1785-L20C15C, D, E, FPLC-5/20C for ControlNet Phase 1.51770-XYC/A
1785-L40C15C, D, E, FPLC-5/40C for ControlNet Phase 1.51770-XYC/A
1785-L60C15DPLC-5/60C for ControlNet Phase 1.51770-XYC/A
1785-L80C15D, E, FPLC-5/80C for ControlNet Phase 1.51770-XYC/A
1785-L46C15E, FProtected PLC-5/40C for ControlNet Phase 1.51770-XYC/A
1785-V30BC, D, EVME PLC-5/30 Controller
32kB Word SRAM
1770-XYV/A
1785-V40BC, D, EVME PLC-5430 Controller
48kB Word SRAM
1770-XYV/A
1785-V40LC, D, EVME PLC-5/40 Controller with Extended Local Port1770-XYV/A
1785-V80BC, D, EVME PLC-5/80 Controller
100kB Word SRAM
1770-XYV/A