RSS File Format — RSLogix 500 Projects
Open RSS Files
in Your Browser
From our work supporting legacy SLC 500 and MicroLogix installations, we know how hard it is to read programs without RSLogix 500. Upload your RSS file and instantly browse ladder logic, data files, and AI explanations.
- RSS files are the native RSLogix 500 project format for SLC 500 and MicroLogix PLCs.
- You can open RSS files online without installing RSLogix 500.
- RSS files contain ladder logic programs, data files, and I/O configuration for legacy Allen-Bradley PLCs.
- plc.company supports all SLC 500 and MicroLogix variants stored in RSS format.
·Updated Apr 1, 2026·PLC Company Engineering
What Is a Rockwell RSS File?
An RSS file is the native project format for RSLogix 500, Rockwell Automation's programming software for SLC 500 and MicroLogix PLCs. The .rss file extension stands for RSLogix Standard Software — it is a proprietary binary format that stores the entire project in a single file.
Every RSS file contains:
- All ladder logic programs (LAD2 through LAD255)
- Data files — integers (N), bits (B), floats (F), timers (T), counters (C), strings (ST)
- I/O configuration and module assignments
- Program documentation and rung comments
- Controller properties and communication settings
Unlike modern ACD files (Studio 5000), RSS files use file-based addressing: every value has a numeric address like N7:0 or B3:0/5 instead of a named tag. This makes RSS programs harder to read without context — which is why AI-powered explanations are especially useful for SLC 500 programs.
For more on how to interpret ladder logic in these files, see our guide on how to read ladder logic, or read the dedicated post on Allen-Bradley SLC 500 programming.
Everything in Your
RSS File, Instantly
Ladder Logic Viewer
See all rungs with color-coded instructions. Inputs, outputs, timers, counters — identified at a glance without opening RSLogix 500.
Data File Browser
Browse all data files (timers, counters, integers, reals) with their current values. Search and filter across all file types.
AI-Powered Explanations
Get plain-English explanations of what each rung does. Useful for audits, knowledge transfer, and understanding unfamiliar code.
Cross-Reference & Signal Tracing
Find every location an address is used across the entire program. Trace a signal from input to output in seconds.
I/O Configuration Viewer
View I/O rack layout, module types, and point assignments. See every device in the system without hardware access.
Safety & Alarm Analysis
Detect safety-critical rungs and alarm conditions in your SLC 500 and MicroLogix programs.
Program Comparison
Diff two RSS versions side by side. See exactly what changed between revisions — rungs added, modified, or removed.
Training Documentation
Auto-generated training documentation covering safety procedures, device reference, alarm response, I/O maps, and daily operations.
Supported Legacy Controllers
Frequently Asked Questions
What is an RSS file?
An RSS file is the native project format for RSLogix 500, Rockwell Automation's programming software for SLC 500 and MicroLogix PLCs. It contains the complete PLC program including ladder logic, data tables, I/O configuration, and documentation.
Can I open RSS files without RSLogix 500?
Yes. PLC Company lets you open and view RSS files directly in your browser without needing RSLogix 500 installed. You can browse all rungs, data files, and get AI-powered explanations of your ladder logic.
Which controllers use RSS files?
RSS files are the project format for SLC 500 family controllers (SLC 5/01 through 5/05) and MicroLogix controllers. RSLogix 500 is the standard programming software for these legacy Allen-Bradley PLCs.
How much does RSLogix 500 cost?
RSLogix 500 licenses vary by version and features, but typically cost $1,500–$5,000+ for a perpetual license. PLC Company provides an alternative for viewing and understanding your programs without needing RSLogix 500.
Is my RSS file secure when I upload it?
Yes. Your RSS file is encrypted in transit and processed on secure, isolated infrastructure. Parsed data is stored in your private account and is never shared with third parties. You can permanently delete your files at any time.
What if I have an older RSLogix 500 version?
plc.company supports RSS files from all RSLogix 500 versions across SLC 500 and MicroLogix controllers. Whether your project is from version 5.x or earlier, we can help you view and understand it.
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