{
  "id": 13083874,
  "title": "Virtual PLC Lab: Ladder Logic Control of a Filling Tank with Factory I/O and OpenPLC over Modbus TCP",
  "url": "https://urgent.news/2026/10/09/virtual-plc-lab-ladder-logic-control-of-a-filling-tank-with-factory-i",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-10-09T09:43:15.000Z",
  "source": {
    "name": "Dev.to",
    "slug": "dev-to",
    "url": "https://dev.to/almahmudkhalif/virtual-plc-lab-ladder-logic-control-of-a-filling-tank-with-factory-io-and-openplc-over-modbus-tcp-4m6e"
  },
  "original_language": "en",
  "account": "The article details the author's attempt to learn PLC programming without owning the necessary hardware. The author realized that a PLC only cares about the I/O image it reads and writes over the network, so they created a virtual rig consisting of a 3D process simulator, a soft PLC, and real industrial protocol (Modbus TCP) between them. The simulator represents the plant, the soft PLC acts like the controller, and Modbus TCP facilitates communication between them. The rig faithfully mimics the Factory I/O v2.5.10 scene, including a tank, inlet valve, outlet valve, two push buttons, and a numeric timer display. The objective is to control the tank using ladder logic, with specific requirements: the fill operation stops after a fixed time, the drain operation also lasts for a fixed time, and the two operations cannot occur simultaneously. The article walks through setting up the process simulator, the PLC, and the connection between them using Modbus TCP. The PLC is configured as a Modbus master and slave, while the simulator is the Modbus server. The author then proceeds to write the ladder logic, which controls the valves, lamps, and timer based on button presses and time intervals.",
  "summary": "I wanted to learn PLC programming, but there was one obvious problem: I don't own a PLC, a tank, valves, or a panel with buttons. Buying that hardware just to practice ladder logic isn't realistic. Then I realised something simple. A PLC doesn't actually care whether the tank is made of steel or pixels — it only cares about the I/O image it reads and writes over the network. So I built a virtual…",
  "key_points": [
    "Author creates virtual PLC lab with 3D process simulator and soft PLC",
    "Modbus TCP enables communication between simulator and PLC",
    "Ladder logic controls tank operations based on button presses and time intervals"
  ],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}