Machinery TwinConnectivity overview
How the twin talks to PLCs, architecture, requirements, and what runs where.
In Online mode, variables with a From Connection config read live values from a PLC. This page explains the moving parts; the per-vendor pages cover setup details.
Architecture
PLC protocols (S7, ADS, OPC UA) are not speakable from a web page, since a browser cannot open raw sockets to your PLC. Machinery Twin therefore uses a small connectivity backend that runs on your computer, next to the scene:
┌───────────────────────── Your PC ─────────────────────────┐ ┌────────┐
│ 3D scene & editor ◄── local WebSocket ──► connectivity │◄──►│ PLC │
│ (browser/app UI) backend │ LAN│ │
└───────────────────────────────────────────────────────────┘ └────────┘The backend polls the PLC at each connection's polling interval and streams value updates to the scene over a local WebSocket. Data flows PLC → twin; your machine stays in charge.
You need the Windows Connector for PLC connectivity
Install the Windows PLC Connector Pro plan and up beside the browser. The browser contains the full editor and simulation; the Connector talks to hardware through a direct encrypted channel.
Supported systems
| System | Protocol | Page |
|---|---|---|
| Siemens S7 (S7-300/400/1200/1500; PLCSIM Advanced direct, Basic via NetToPLCSim) | S7 communication | Siemens S7 |
| Beckhoff TwinCAT 2/3 | ADS | Beckhoff ADS |
| Anything with a UA server (including the above) | OPC UA | OPC UA |
A connection's common settings
Every connection, regardless of type, has: a name (referenced by variables, rename with care), an enabled toggle, a polling interval in milliseconds, and a live status indicator. Each also has a Test button, see Testing & diagnosing.
Polling interval
The interval is per connection: 50–100 ms reads as live motion; 500+ ms is fine for status displays. Put fast axes and slow status tags on two connections to the same PLC with different intervals if you need both.
Network requirements
Your PC must reach the PLC over the network (same subnet or routed). Nothing is exposed publicly and no cloud is involved, traffic stays on your LAN.