> 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-knx-library/description.md).

# Description

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The HVAC KNX Library enables retrieving KNX IP data directly from the program via KNX IP interfaces using UDP. For this purpose, the master function block is placed and the individual group address function blocks are linked to the master.
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***

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

<a href="/spaces/ltcbXgy6Y2teLoU01eGk/pages/f39b4b7947d8d3597c3f5a0b4ed099bec53ab1e9" class="button primary" data-icon="up-right-from-square">Download</a> <a href="https://store.codesys.com/en/hvac-knx-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>

{% hint style="info" %}
**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).
{% endhint %}

### Overview

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<figure><img src="/files/32a6c4044d70c3990c1aad4a17a7c84a6ad7520d" alt=""><figcaption></figcaption></figure>

<p align="center"><em>Function blocks optimized for practical use. Easy use of KNX with a master function block and a slave function block.</em></p>
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***

### Description

The HVAC KNX SL includes function blocks for KNX communication and is specially optimized for the CFC editor. A master block (Master UDP) serves as the base to which "slave" blocks are connected. These blocks are connected to each other via an interface. The library includes DPT read and write blocks as well as the most common DPT datapoint function blocks.

Configuration is done directly on the block without additional mapping by entering the group address. The KNX IP interface monitors the bus, so the data appear at the block in the correct format immediately. When sending, care must be taken not to cause "flooding" on the KNX bus in order to avoid speed and response issues in the KNX network.

{% hint style="info" %}
**Supported devices (KNX IP interfaces):**\
\
The following KNX IP interfaces have been successfully tested with the library.\
In addition, in many cases other KNX IP interfaces not listed here should also work without problems, even if they have not yet been explicitly tested.
{% endhint %}

| Manufacturer | Device         | Notes |
| ------------ | -------------- | ----- |
| ABB          | IPS/S 3.1.1    |       |
| SIEMENS      | SWG1 148-1AB22 |       |
| MDT          | SCN-IP000.03   |       |

***

### Details

| **Documentation Version**      | <code class="expression">space.vars.HVACKNX\_Library\_latest</code> |
| ------------------------------ | ------------------------------------------------------------------- |
| **Placeholder**                | `HVACKNX`                                                           |
| **Available in 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 KNX SL](https://store.codesys.com/de/hvac-knx-sl.html)        |

***


---

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