Rockwell PLC Program Viewer (ACD, RSS, L5X to PDF) (Beta)

Open Allen-Bradley PLC programs without Studio 5000 or RSLogix

A machine arrives with its PLC program on a USB stick, an old laptop dies, or a supplier sends a project and you have no Logix Designer or RSLogix licence at hand. Upload the project file and get a printout that reads like the one Rockwell software makes: ladder rungs drawn with rails, contacts, coils, branches and instruction boxes, the rung comments and tag descriptions above each operand, then structured text, function block sheets, SFC charts, the tag database and a cross reference. The same content comes as a searchable HTML viewer that works offline, as tables, and for ACD files as an L5X export.

What to upload

A .zip holding one of these files works as well; the project file inside is found by itself.

What you get

• Printout (PDF) with a contents page and bookmarks: controller or processor information, every routine or ladder file in program order, then tags, data types, Add-On Instructions, modules and tasks (Logix) or data files, address descriptions and I/O (RSLogix 500), and a cross reference of every tag or address. Letter or A4.
• Viewer (HTML): one file with the project tree on the left, the drawn rungs on the right and a search box for tags, addresses and comments. It needs no internet connection.
• L5X for ACD projects, with the data types, modules, tags, Add-On Instructions, programs, routines and tasks of the project.
• Program as ASCII text (.SLC) for RSLogix 500 projects: every rung in the SOR ... EOR mnemonic form with branches as BST ... NXB ... BND, plus the values of the integer, bit, timer, counter, control, float and long data files. The symbols and descriptions come as an .EAS comma separated file.
• Tables: tags or addresses with descriptions, all comments, and the cross reference as CSV, and one Excel workbook with sheets for routines, logic, tags, comments, data types, I/O and the cross reference.

The result page shows a summary, the list of routines and the first routine drawn, so you can check the file before downloading anything.

Studio 5000 projects (.ACD)

Ladder rungs come with their comments, structured text keeps its line numbers, function block sheets are drawn with their blocks, references, connectors and wires, and SFC charts with steps, transitions, actions and branches. Tags show their data type, description, member comments and alias target; Add-On Instructions their parameters and local tags; modules their catalog number and slot or address where the project records them. Tag values are read from L5X and L5K exports; from an ACD file the tool reads the tag definitions but not the stored values.

The ACD files saved with version 24 that we have seen keep their database in an encoded form. The tool says so, and an L5X saved from that project (File, Save As) opens instead. We had no ACD files from versions 21 to 23 and 25 to 27 to test with.

RSLogix 500 projects (.RSS)

Each ladder file is drawn with its rungs, branches and instruction boxes, the values shown under the parameters, the rung comments, and the symbol and description of every address. The printout lists the program and data files, the values of the data files, the full documentation database and, for MicroLogix 1100, 1200 and 1400, the expansion I/O modules. Instructions that appear only rarely in the projects we tested with are named by their code (for example OP2B) and keep their operands, and the result page lists them.

RSLogix 5 projects use the same kind of container. They are read the same way, but we had no real .RSP file to test with, so check the printout against the project.

Comparing two versions

Upload the older file as the PLC program and the newer one under "Second version to compare". The comparison report (PDF, HTML and Excel) lists added, removed and changed programs, routines and rungs (each changed rung drawn before and after), structured text lines, tags, data types, Add-On Instructions, modules, tasks and comments. For RSLogix 500 projects it also lists changed symbols, descriptions and data values. The two files may be in different formats, for example an ACD and an L5X export of it.

What is not shown

Routines and Add-On Instructions protected with Source Protection are stored encrypted: they are listed with their names, but not their logic. Function block wiring that cannot be decoded completely is drawn with numbered pins and left out of the L5X; the result page names such routines. A file that is cut off or damaged gives a message saying so instead of a partial printout.

Privacy

Files are processed on our server only to produce your downloads, and the results are deleted automatically after 30 minutes. Program names, tag names and comments never go into our statistics.