BACnet1: Integrating BACnet devices and their objects

The NETx BMS Server provides a BACnet/IP client interface which can be used to integrate BACnet devices and their objects. In addition, non BACnet/IP devices that use other BACnet media (e.g. BACnet MS/TP, BACnet over LonWork, ...) can be integrated too. For these non-IP devices, corresponding BACnet/IP routers have to be available.

Compared to other technologies, BACnet does not provide a vendor-independent management tool for configuring and maintaining BACnet devices – each vendor has its own tool for engineering their devices. However, BACnet on the other hand provides device management services which can be used to discover BACnet devices and their objects online – only an IP connection to the BACnet network has to be available.

For discover BACnet devices and their objects, the NETx BMS Server provides a tool called BACnet Explorer. This tool can be started from the NETx BMS Studio when NETx BMS Server is not running.

To start the explorer, shutdown the NETx BMS Server and select "Start Explorer ..." from the "BACnet" menu within the NETx BMS Studio.

Afterwards, the BACnet Explorer is starting. If it is the first time that the BACnet Explorer is used within a BMS Workspace, the BACnet Explorer for the local IP address that shall used for communicating with the BACnet network. If you have multiple IP addresses please select the one that is used to communicate with the BACnet network.

Then, the user interface of the BACnet Explorer is shown. It will automatically start to search for BACnet devices. After a few seconds, all available BACnet devices (IP and non-IP ones will be listed). The following figure shows an example:

As next, select the devices that you want to integrate. After having selected a device, the BACnet Explorer will search for all objects that are available within the device and which are supported by the NETx BMS Server.

Select and deselect the objects that you want to include or exclude. After having chosen all BACnet devices and objects that you would like to integrate, choose at the bottom right of the Explorer whether you want to replace the old configuration ("New..") or whether you want to attach the devices and objects to the existing one ("Attach ..."). By clicking on the "Export" button the device and object configuration will be stored within the active workspace of the NETx BMS Server.

Afterwards, close the BACnet Explorer by pressing the "Exit" button and change back to the NETx BMS Studio. Start the NETx BMS Server again and open an Item Tree. All BACnet devices and objects are found under the sub tree "NETx\XIO\BACnet". Each device has one entry within the Item Tree. Below this entry, you will find a GATEWAY item which shows the connection state to the BACnet device. In addition, all selected objects are listed. As defined by the BACnet standard some BACnet objects are readonly (e.g Binary Input, Analog Input, ...) and some are also writable (e.g. Binary Output, Analog Output, ...). Input objects have only one item which shows the current Present Value of the BACnet object. Output objects have in addition for each used BACnet priority one Write Item (used to send a write command with the given priority) and one Reset Item (used to reset the given priority again). The NETx BMS Server supports multiple priorities at the same time. The following figure shows an example.

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