> For the complete documentation index, see [llms.txt](https://support.powerio.com/hub/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.powerio.com/hub/codesys-hvac/en/hvac-modbus-library/description.md).

# Description

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<figure><img src="/files/c73151b01b9718def457f9ad86827443cb7c8a16" alt="" width="100"><figcaption></figcaption></figure>
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The library contains manufacturer-specific function blocks that can be used without having to configure the registers. This enables rapid engineering in plant programming for many Modbus devices.

Matching visualization elements for the function blocks can be found in the HVACV Visu library.
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***

To help you get started right away, we offer the library as a download. A license can be purchased via the CODESYS Store. If you need further support, please do not hesitate to contact us.

<a href="/spaces/ltcbXgy6Y2teLoU01eGk/pages/2de568655616943d978126800c761d884d12f130" class="button primary" data-icon="up-right-from-square">Download</a> <a href="https://store.codesys.com/de/hvac-building-process-automation-sl.html" class="button secondary" data-icon="seal">Purchase license</a> <a href="https://www.powerio.com/de/kontakt" class="button secondary" data-icon="question">Get support</a>

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**Licensing:**

Without purchase of a license (only *Download*) the library runs for **30 minutes as an unrestricted trial version**. For productive use a Single License (SL) / single-device license is required per controller.\
For instructions on installing licenses, please visit the page [Product Licensing](/hub/codesys-hvac/en/overview/licensing.md).
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***

### Overview

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<div align="left"><figure><img src="/files/3ec6ecb0db8fc6e35dc0233bada08022bb30cf8d" alt="" width="263"><figcaption></figcaption></figure></div>

*Use visualization elements for Modbus devices.*
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<figure><img src="/files/d8fa167d7366d1c6a6a64c8727dc3518b0d0e63e" alt=""><figcaption></figcaption></figure>

*Simple engineering by placing a master block for communication.*
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<figure><img src="/files/59c3c6671842fe24df22b210afefd12cf103b58d" alt="" width="281"><figcaption></figcaption></figure>

*Modbus client with TCP support.*
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<figure><img src="/files/47bc9b1a3eacf63384b3588c925d93ff88fcafe2" alt=""><figcaption></figcaption></figure>

*Modbus client with serial support for Modbus RTU.*
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***

### Description

The library is optimized for use with the CFC editor. Slave devices are connected via a master block (serial or TCP). Slave devices can be individual Modbus queries or fully finished device blocks from many manufacturers. This simplifies commissioning.

{% hint style="success" %}
**Is a device missing in the HVAC Modbus Library?**

If you need a device that is not yet included in the HVAC Modbus Library, just contact us. After a brief internal coordination, we will be happy to expand the library for you and provide you with the corresponding device as quickly as possible.
{% endhint %}

***

### Details

| **Documentation Version**          | <code class="expression">space.vars.HVACMODBUS\_Library\_latest</code>                                       |
| ---------------------------------- | ------------------------------------------------------------------------------------------------------------ |
| **Placeholder**                    | `HVACModbus`                                                                                                 |
| **Available in the CODESYS Store** | *Yes*                                                                                                        |
| **Programming system**             | *CODESYS V3.5.17.2 or higher*                                                                                |
| **Runtime system**                 | *CODESYS Control V4.2.0.0 or higher*                                                                         |
| **Licensing**                      | *Single License (single device license)*                                                                     |
| **License**                        | [HVAC Building Automation Package SL](https://store.codesys.com/de/hvac-building-process-automation-sl.html) |

***


---

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