In order to configure the BACnet driver, a channel is first required to be setup and started by setting enable to yes and pressing the start button for the selected Channel. For most sites, a single channel is sufficient, however, up to 4 channels can be configured to distribute the load.
Each channel requires an unique NIC/Port Number, and if a single NIC Adapter is available then each channel would need a different port number. If 4 NIC Adapters are available, then each NIC can use the same port number.
Once the BACnet driver has been successfully installed, it is possible to scan for devices on a specified channel. A channel acts as a basic building block of a BACnet network with an unique adapter (IP) and a port. The BACnet tab in the Administration panel allows you to configure the channels. .png)
BACnet uses UDP for messaging over ethernet and there is a limitation for sending broadcast messages which means a device scan only works when all devices are on the same port.
The default port number for BACnet/IP is 47808 and most sites will be setup to use this port number on all devices, and in this case, a device discovery will locate all the devices.
UDP broadcast messages are also limited to the same subnet, which means a device scan will not locate devices on another network. To overcome the device scan limitations, the BACnet driver supports static address bindings and BACnet Broadcast Management Devices (BBMD).
When a BBMD is used, broadcast messages are sent directly to the BBMD which retransmits the message to other BBMDs and onto its local subnet. When BBMD’s are present, the IP address of the BBMD can be configured into the channel and then a device scan will locate all devices connected to the BBMD. If a BBMD is not present and BACnet devices are on a different subnet or a on a different port then static address bindings are required and each device must be added manually into deviceWise.
Channel 0/Channel 1/Channel 2/Channel 3
Enter the following details for each channel up to 4 channels you want to connect:
| Field | Description |
|---|---|
| State | Shows the state of the Channel. You will be able to start a channel after entering all the required information in the respective fields. |
| Enable | Select Yes to enable the channel. |
| UDP Port | Enter the UDP port of the channel. |
| BBMD Address | BACnet Broadcast Management Device (BBMD) Address |
| Local deviceWISE Device ID | Enter the deviceWISE Device ID. This Device ID is the identification of deviceWISE in the BACnet network. |
| Apdu Timeout | Application Protocol Data Unit (APDU) Timeout |
| Apdu Segment Timeout | Application Protocol Data Unit (APDU) Segment Timeout. |
| Number of retries | The number of retries to be made to connect to the device channel. |
| Write Priority | Sets the default write priority value for all devices created on this channel. It is possible to use other priorities if the BACnet Priority Write action is used. |
Device Scan
During commissioning the device scan is used to discover all BACnet devices on the network to automatically create a corresponding deviceWISE device. Only devices connected to the same segment, connected to a router on the same segment or connected to a BBMD will be discoverable using this method. A BACnet WhoIs message is sent when the Device Scan is initiated. For each IAm message received, a deviceWISE device is created. The device will be started at this moment if the option is set.
| Field | Description |
|---|---|
| Scan Channel 0 | If it is set to No, the associated channel will not be scanned when you Scan the Network. |
| Scan Channel 1 | |
| Scan Channel 2 | |
| Scan Channel 3 | |
| Low Limit | The device scan is limited to a single device or a range of devices using the High and Low Limit. |
| High Limit | |
| Start BACnet devices when found | If it is set to Yes, it will start the corresponding deviceWISE device when an IAm message is received. |
| Regenerate BACnet device variable tree when found | If it is set to Yes, it will remove the existing JSON file and regenerate the file by reading from all of the devices within the device. When this is set to No, only new BACnet devices discovered on the network will be automatically added to deviceWISE. |
| Use static address bindings | Enable or disable static address bindings. For more information on static address bindings, see BACnet / IP driver - Version 3. |