> For the complete documentation index, see [llms.txt](https://infosys.selmotech.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://infosys.selmotech.com/selmo-solution/selmo-solution-en/selmo-documentation/4-structure-of-the-machine-static/plant.md). # Plant This chapter describes the **Plant** as the top structural level in the Selmo system.\ The goal is to **understand the entire plant as a unit** – independent of individual processes or stations. The Plant forms the **global framework**in which all other elements exist. *** ### Role of the Plant The **Plant** represents the **entire machine or plant**. It is: * the top level in the Selmo model * holder of global states * place for plant-wide monitoring * not responsible for processes The Plant: * describes **no sequences** * contains **no state machines** * makes **no process decisions** > **The Plant defines the framework –**\ > **not the behavior in detail.** *** ### Global states At the plant level, states are described that: * apply to the entire plant * are independent of individual hardware zones * are not tied to a specific process Typical global states are: * plant ready / not ready * plant released / locked * overall fault * global safety state These states: * are visible to all subordinate levels * influence their behavior indirectly * are **not** controlled by sequences > **Global states describe the plant context,**\ > **not the process state.** *** ### Plant-wide CMZ Certain conditions must **be valid for the entire plant at all times** be. These are modeled as **plant-wide CMZ (Constantly Monitoring Zones)** . Examples: * main power supply * central protective devices * overarching safety releases * plant-wide emergency stop states Characteristics of Plant CMZ: * permanently active * state-independent * override all subordinate levels In case of a deviation: * automation is locked plant-wide * all hardware zones react deterministically * there are **no movements possible anymore** > **Plant CMZ protect the integrity of the entire plant.** *** ### Distinction from hardware zones For clear classification: * **Plant** * describes the entire plant * manages global states * contains plant-wide monitoring * **hardware zone** * describes a part of the plant * manages operating modes * starts and stops sequences > **The Plant knows no processes.**\ > **Hardware zones know no entire plant.** *** ### Placement in the overall model The hierarchical structure is: Plant\ └─ Hardware Zone\ └─ Sequence\ └─ Zone The Plant: * is above all hardware zones * forms the stable upper closure of the model * enables clear hierarchy and escalation *** ### Summary The Plant is: * the structural representation of the entire plant * holder of global states * place for plant-wide CMZ * deliberately free of process and detail knowledge > **The Plant creates order at plant level –**\ > **so that what is modeled below can be clear.** --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://infosys.selmotech.com/selmo-solution/selmo-solution-en/selmo-documentation/4-structure-of-the-machine-static/plant.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.