PLEXUS PLC Software Features
Every tool automation engineers need — PLC connectivity, encrypted code management, live monitoring, SCADA building, ISA-18.2 alarm management, and intelligent code analysis — in one industrial automation platform.
Connectivity
Universal PLC Connect
Connect any PLC brand in under 2 minutes
PLEXUS PLC software connects directly to any PLC using native protocols — no middleware, no OPC server, no proprietary gateway hardware required. Allen-Bradley ControlLogix and CompactLogix via EtherNet/IP (CIP), Siemens S7-300, S7-400, S7-1200, and S7-1500 via S7comm and S7comm+, Schneider Modicon and any Modbus slave via Modbus TCP/RTU, any OPC-UA server, Omron CJ and CS series via FINS over UDP/TCP, and Mitsubishi MELSEC via MC Protocol 3E/4E. BACnet/IP and DNP3 are also supported for building automation and utility applications.
Supported Protocols
Code Management
Encrypted PLC Code Vault
Centralised, AES-256-GCM encrypted program repository
The PLEXUS Code Vault stores PLC programs in an encrypted repository. Each file is encrypted with AES-256-GCM in the browser before upload — decryption keys never leave your device. Supported formats include Allen-Bradley L5X and ACD, Siemens XML, Omron CXP, and Schneider ZAP. Version history is maintained for every program — view a diff between any two versions, restore any previous version in one click, and download with instant in-browser decryption. Syntax highlighting, search, and full audit trail are included.
Supported File Formats
Code Quality
AI-Powered IEC 61131-3 Linter
10+ static analysis rules for Ladder Logic, ST, FBD
The PLEXUS PLC linter analyses uploaded programs against IEC 61131-3 rules and industrial best practices. Rules include: duplicate output coils (Ladder Logic — a common cause of unpredictable machine behaviour), missing emergency-stop interlocks, dead rungs (unreachable logic), unreset timers that accumulate across PLC scans, off-scan output coils, outputs driven by contacts on the same rung (potential race conditions), and more. Each finding includes an AI-generated plain-English explanation and a concrete fix suggestion — not just a line number.
Lint Rules
- ▸Duplicate output coils
- ▸Missing E-Stop interlock
- ▸Dead rungs
- ▸Unreset timers
- ▸Off-scan outputs
- ▸Race conditions
- ▸Naming convention violations
- ▸Missing documentation
Visualisation
SCADA/HMI P&ID Builder
ISA-5.1 compliant P&ID screens with live PLC data
The PLEXUS SCADA builder lets engineers design P&ID (Piping and Instrumentation Diagram) screens using a library of ISA-5.1 and IEC symbols. Pumps, valves, tanks, conveyors, motors, sensors, and 50+ more symbols are included. Drag-and-drop canvas with pipe routing, label placement, and colour-coded status indicators. Each element is bound to a live PLC tag — when connected, the actual process values animate directly on screen. Screens are version-controlled and can be exported or shared with operators.
Data
Tag Historian & Live Monitoring
Time-series tag data with real-time graphs
PLEXUS captures time-series data for every monitored PLC tag and stores it in a PostgreSQL-backed historian. Tag values are sampled at configurable intervals (minimum 500ms), buffered in the browser, and flushed to the server on a schedule — with sendBeacon() ensuring the final batch is never dropped on page close. The historian viewer supports raw, 1-minute average, 15-minute average, and 1-hour aggregate views. Data retention is enforced server-side (90 days default). The tag database is ISA-5.1 compliant with CSV import/export and automatic engineering unit assignment.
Safety
ISA-18.2 Alarm Management
Raise, acknowledge, shelve, and escalate alarms
PLEXUS implements the full ISA-18.2 alarm lifecycle: Raised → Acknowledged → Cleared, with shelving (temporary suppression with mandatory expiry), re-alarm detection, and escalation. Alarm definitions include setpoint, deadband, delay, severity (Low / High / Critical / Emergency), and expression-based conditions. Unacknowledged alarms older than 15 minutes trigger automatic escalation notifications to company administrators — enforced server-side via pg_cron so a disconnected browser never silences an alarm indefinitely. Full alarm event history is retained for 365 days for compliance reporting.
Operations
Automated PLC Backup & Restore
Daily encrypted backup with one-click restore
PLEXUS schedules automated daily backups of all PLC programs, tag databases, network device configurations, and SCADA screens. Backups are encrypted with AES-256-GCM and stored in Supabase Storage. The restore wizard verifies the backup integrity before applying, shows a diff of what will change, and requires explicit user confirmation before writing any data. Backup history is retained indefinitely — roll back to any point-in-time snapshot. Manual on-demand backups can be triggered at any time.
Ready to try PLEXUS PLC Software?
Free trial, no credit card. Connect your first PLC in under 2 minutes at plexus-plc.com.