BACnet Server

This section provides background information about BACnet Server. For procedures or workflows, see the step-by-step section.

Overview

BACnet Server functions as a gateway that allows you to monitor and control Desigo CC objects through BACnet. You can use BACnet Server to create virtual devices and then display any Desigo CC objects and properties as BACnet objects. Virtual devices are useful for logically grouping objects corresponding to organizational structures, floor plans, and physical devices.

For example, you might have a multi-floor research center with thermostats on each floor controlled by different physical devices. You can drag the objects from those devices into one virtual device named Research Center Thermostats to monitor and control the thermostat objects from one convenient location in System Browser.

Security Consideration

Be careful about exporting validated or fire system objects that might invalidate a UL listing or other standard. By default, all exported objects are read only, but you can configure write access for them if needed.

System Limitations

Maximum exported objects: 20,000

Network Considerations

Use the following guidelines when configuring the connection settings:

BACnet Server requires at least one physical network and one virtual network.
A BACnet connection must have a unique combination of IP address and UDP port. For example, if you have a BACnet driver at address 1.2.3.4 and port 47808, you cannot have the BACnet server with the same settings. However, you can have the following:
- Different IP address or a different port—1.2.3.4 and 47809 (or, 1.2.3.5 and 47808)
- Different IP address and a different port—1.2.3.5 and 47809.

Scenario 1

If you want the BACnet driver and the BACnet server to communicate with each other, give the BACnet server a different IP address on the same IP segment and use the same port—for example, 1.2.3.5 and 47808. In this case, you do not need a BBMD because the addresses are on the same IP segment. As long as you are not using DHCP, you can assign a second IP address to the same NIC in Windows Network Connections.

Scenario 2

If you want the BACnet driver and the BACnet server to communicate with each other, and you are using DHCP, you can use a second NIC on the same network so that you get another IP address from the same segment. Alternatively, you can use the same IP address but a different port. Once you use a different port, you need a BBMD to bridge the two ports. Since the BACnet server cannot be a BBMD, you have to configure the BACnet driver to be the BBMD.

Scenario 3

If you do not want the BACnet driver and the BACnet server to communicate with each other, you can use a different IP address and the same port on a different segment. Alternatively, you can use the same IP addresses and different ports. Do not setup a BBMD to bridge the ports.

Scenario 4

If you want the BACnet server to communicate with a BACnet network on a different subnet, you must have a BBMD configured on each subnet. Since the BACnet server cannot be a BBMD, you must configure other devices as the BBMD. For example, you could configure the BACnet driver to be a BBMD on the segment that the BACnet server is on and then configure a device on the other segment to be a BBMD. There can be only one BBMD per network segment.

Workspace

The BACnet Server workspace consists of several sections available from the BACnet Server tab. The sections that display are determined by your selection in System Browser.

BACnet Server Connection Configuration

Selecting BACnet Server in System Browser allows you to add a network connection to the management platform and configure the connection properties.

BACnet Server Settings
Field	Description
Port ID	A unique ID.
Network number	A unique number.
Protocol	The protocol selected, either IPv4 or Virtual, when you add a new network type.
Add	Adds a new network type to the table.
Remove	Removes a network type from the table.

Connection Properties
Field	Description
Port ID	The Port ID for the currently selected row in the BACnet Server Settings table. This field is editable with a value of 1 – 254..
Network number	The Network number for the currently selected row in the BACnet Server Settings table. This field is editable with a value of 1 – 65534.
Enabled	Enables this port in the BBS configuration (the BT BACnet Stack). If there are multiple ports, you can enable or disable this port.
Adapter	The hardware adapter used by this server. Visible only for IPv4 connections.
IP address	The IP address used by the adapter. Visible only for IPv4 connections.
UDP Port	The UDP port used by the adapter. Visible only for IPv4 connections.

BACnet Server Devices

Selecting BACnet Server in System Browser allows you to view virtual device status and name.

BACnet Server Devices
Field	Description
Device Status	Status of the virtual device. Possible values are `Unknown`, `Stopped`, `Running`, and `Configuration Error`. For configuration errors, see the Troubleshooting section.
Device Name	Name of the virtual device.

BACnet Server Device Settings

Selecting a virtual device in System Browser allows you to edit the device settings.

BACnet Server Device Settings
Field	Description
Device Name	A unique name on the BACnet network.
Device Instance	A unique number on the BACnet network. Acceptable values are 0 – 4194303.
Device Description	Displays the description of your choice.
Device enabled on startup	When selected, the device starts automatically when the project starts. When cleared, the device does not start up automatically and will not appear on the BACnet network.
Device is read only	When selected, the points in the device will not be commandable and alarms cannot be acknowledged. When cleared, the points in the device will be commandable and alarms can be acknowledged.

Notification Classes

A notification class is a list of devices (recipients) that receive alarms and alarm acknowledgments when an object enters an alarm condition.

Notification Classes
Item	Description
Notification Class Entries Table	Add: Adds an entry in the Notification Class Entries table. Remove: Removes a selected entry in the Notification Class Entries table. Instance No.: The number entered in the Instance No. field. Priorities: The priorities selected in the Priority fields. # of Recipients: The number of devices registered to receive alarms and alarm acknowledgements.
Notification Properties Section	Instance No.: The instance number distinguishes an object from other objects of the same type within a device. Priority: Allows selection of the following alarm states: - To Off Normal: Valid range is 0 through 255. - To Fault: Valid range is 0 through 255. - To Normal: Valid range is 0 through 255.

Recipients

A Recipient is a device that receives alarms and alarm acknowledgments when an object enters an alarm condition.

Recipients
Item	Description
Notification Class	Displays a list of Notification Classes from the Notification Class Entries table.
Recipients Table	Add: Adds a recipient selected to the Notification Class selected from drop-down list to the table. Remove: Removes a selected recipient based on one of the following choices: Remove this recipient from this NC Remove this recipient from all NCs in this virtual device Remove this recipient from all NCs in all virtual devices Copy: Copies a selected recipient based on one of the following choices: Copy to all NCs in this virtual device Copy to all NCs in all virtual devices NOTE: There are scenarios in which the copied recipient will overwrite an existing recipient in another notification class. This applies to each of the recipient types—Device Instance, Address, and Broadcast. For example, you copy Device Instance 552 (which has To Fault selected) to another notification class with a recipient that also has Device Instance 552 in it (with To Off Normal, To Fault, and To Normal transitions selected). The result is that the copied recipient overwrites the existing recipient data. In other words, the To Off Normal and To Normal transitions will no longer be selected, and you will need to manually select those transitions if you still want them. Process ID: The number entered in the Process ID field. Recipient Type: The device receiving alarms and alarm acknowledgements. Transitions: Lists the alarm states To-Offnormal, To-Fault, and To-Normal.
Recipient Properties	Device Instance: A number that uniquely identifies a device on a BACnet network. Address: - MAC Address (Hex): Must use an even number of 2 to 12 alphanumeric characters, including 0 through 9, and A through F as either upper- or lower-case letters. For example, a5030756BAC0 is a valid BACnet/IP address using the hexadecimal form. - Network No.: A unique number that identifies one network (where devices reside) from another network on the BACnet Internetwork. Broadcast: - Local: Send alarm information to all devices on the local network. - Remote Network No.: Send alarm information to all devices on a specified (single) remote network. You must enter the remote network number. - Global: Send alarm information to all devices on all networks within the BACnet internetwork.
Recipient Process	Process ID: Consult the vendor to obtain the Process ID for the devices you are integrating. This field is required. The Process ID, along with either the Device Instance number or the MAC address and network number, is needed to send alarms to BACnet devices.
Transitions	To Offnormal: Checked by default. Lists this alarm state as true in the Recipients table. To Fault: Checked by default. Lists this alarm state as true in the Recipients table. To Normal: Checked by default. Lists this alarm state as true in the Recipients table.

Trend Logs

BACnet Server collects new trends every 5 minutes (the minimum), which accounts for the lag between reading trends from the HDB and then displaying them in BACnet trend log objects.

A client of the BACnet Server can ask for trend data in one of three ways: by sequence number, by position, or by time. Trend functionality is subsystem independent.

You can drag and drop offline or online trend log objects from System Browser to the Trend Logs section and then configure them. You cannot drag and drop objects from Trend View Definitions folder. See the following image.

NOTE: Before you configure the Trend log in BACnet Server, make sure there is trend data in the HDB for the object you want to export. BACnet Server needs this information to find the point that the trend log is mapped to. This applies to all offline trend definitions.

Trend Logs
Field	Description
Enable	When selected, allows communication with the database. When cleared, prevents communication with the database.
Name	Displays the System Browser name of the trend object. You can edit this field.
Instance	A unique number automatically assigned to a trend log. You can edit this field.
Description	Displays the System Browser description of the trend object. You can edit this field.
Notification Class	Allows you to assign a notification class to receive the buffer (threshold reached) full alarm notifications.
Full Alarm	When selected, notifications are sent when the threshold is reached When cleared, notifications are not sent when the threshold is reached, and the Threshold field is disabled.
Threshold	The threshold is based on the buffer size. Min = 10% of buffer size Max = any value less than buffer size Example: A trend has a buffer size of 1000. The Min is 100; the Max is 999.
Buffer Size	By default, an entry in this field automatically sets the threshold number to 80% of the buffer value unless the Full Alarm field is cleared. However, you can modify the Threshold number according to stated parameters if the Full Alarm field is selected. Min = 10 Max = 10,000 Example: You enter 5000 in the Buffer Size field; the Threshold field automatically changes to 4000.
Update Rate (min)	The interval used to collect and record values for the object. Min = 5 minutes Max = 1440 minutes (1 day)
Object Property Reference	The object and property associated with (mapped to) the trend.
Path	Displays the location of the object in the building control system.
Remove	Removes the selected object(s) from the device.

Device Point Mapping

Selecting a virtual device in System Browser allows you to add and remove points, and modify several other fields. Instances can be dragged from System Browser, and the default property will be the default property of the object model.

Device Point Mapping
Field	Description
Enable	When selected, the object appears with its associated device on the BACnet network. When unselected, the object does not appear on the BACnet network.
Name	Displays the name of your choice.
Instance	Displays the device instance number. Acceptable values, which must be unique on the BACnet network, are 0 – 4194303.
Type	Displays the BACnet object type.
0 Base	Displays a checked box if a Desigo CC multistate object is mapped to a BACnet object, and the property selected for the mapping is assigned a text group with zero as the base value. BACnet is not able to read zeros, so it increments each value in the text group associated with the property by one. For example, the present value property of a supply fan object assigned to a text group with the integer values 0, 1, & 2 are indexed to 1, 2, & 3 and displayed this way on the BACnet network.
Alarmable	When selected, a BACnet object in the virtual device is alarmable with all the required properties of any other alarmable object. When unselected, a BACnet object in the virtual device is not alarmable.
Description	Displays default text, which is editable.
Notification Class	The recipients to send alarms to.
Property	Displays a list of properties available for mapping to each object type.
Path	Displays the location of the object in the building control system.
Discipline	Displays the discipline assigned to the object.
Remove	Removes the selected object(s) from the device.

BACnet Server Toolbar

Icon	Description
	Saves changes to the configuration or device.
	Starts device(s).
	Stops device(s).
	Restarts device(s).
	Deletes selected device.

Priority Mapping

The Priority Mapping feature allows you to map BACnet priorities to other subsystem priorities.

Command Priority

Some objects in your building control system use specialized command priorities to determine whether an operator or a particular control program is in control. The Present Values of six object types in your building control system are based on a command priority and established in a hierarchy that ranks from highest (1 – Manual Life Safety) to lowest (16 – Available). The six object types are Analog Output, Analog Value, Binary Output, Binary Value, Multi-State Output, and Multi-State Value. The hierarchy helps determine which source has priority over another to change the value of an object. To command one of these object types, you—or an application—must have a command priority equal to or greater than the current command priority of the object.

Command Priority Array

A Command Priority Array displays commands that have been issued at various priority levels (for example, 8 = Manual Operator). Users and applications can set or relinquish (release) commands for a commandable object. If the Present Value of an object has a Command Priority Array, the appropriate priority level is commanded or relinquished when a command is executed. If the Present Value of an object does not have a Command Priority Array, the system overwrites the present value with the newly commanded value. You can command or relinquish any priority level that you have access to, based on your user privileges.

Command Priority Map

Each subsystem priority array will differ. Each likely has commands mapped to a number—and those numbers need to be mapped to the BACnet priorities.

The following image shows how a Command Priority Map might look for a subsystem. In the example, external priority 35 equals OPER (BACnet Priority 8), 34 equals SMOKE, 32 equals EMER, and so on.

Default Command Priority field

This editable field uses a default command priority to provide a priority value when there is no priority array and the selected command expects a priority.

Template uses this priority map check box

If this check box is not selected, the library mapping template uses the default command priority value.

If this check box is selected, the library mapping template uses the priority map from the following location in the Management View:
Project > System Settings > Libraries > L1-Headquarter > BA > Device > APOGEE_P2_BACnet_Server

Library Mapping

The Library Mapping feature allows you to do the following:

Map any Desigo CC objects to BACnet objects, property by property
Map multiple instances of the same object, if different Present Values are used—for example, Phase 1, Phase 2, Phase 3
Map Desigo CC alarms to BACnet alarms
Enable alarming on templated objects (non-templated objects only support sending a value and commanding)
Command and release supported properties
Select bit strings for status flag properties, and also enter numerical values for some other properties
Customize the Headquarter default template for use at the project level
Add more object types to the Library Mapping template provided by Headquarter, or add more properties to existing object types
Clone the default template for use at the allowed customization level
Create a library-only EM to deliver a mapping template for several object models that belong to a specific subsystem. This can reduce labor on jobs if many sites have the same subsystem and want to use the BACnet Server.

When BACnet Server is installed, the associated library provides mapping for a device’s default value. If you want more detail, you can map your device objects using the BACnet Server Library Mapping feature, which is preinstalled with Headquarter defaults for object models and their associated properties.

Object Models and Properties

Each object model shows only properties that can be mapped to that type. If the Alarmable check box is selected for the object type, the Mapping Details section lists all available source properties. If the Alarmable check box is not selected for the object type, the Mapping Details section lists only non-alarmable BACnet properties.

NOTE: If you enable alarming on an object model in a template, all instances of that object model will be alarmable.

Property selection affects behavior in the following ways:

Property Type	Behavior
Default Value(s)	BACnet Server determines the mapping.
Not Applicable	BACnet Server does not display the property.

Properties and Commands

The following properties and commands display in the Extended Operation tab.

Property	Description	Commands
Status	Shows default values: `Unknown`: The BACnet Server is not configured. `Stopped`: The BACnet Server is not running and not communicating with the network. `Running`: The BACnet Server is running and communicating with the network. `Configuration Error`: The BACnet Server is not properly configured and is not communicating with the network.	Start Stop Reset
Summary Status	Highest priority status that is currently active for an object.	—
Alarm Suppression	When this feature is enabled for specific system objects, any alarms coming from those objects are suppressed in the management platform.	Enable Disable Enable All Disable All
Active COV Subscriptions	The total number of objects actively receiving COV subscriptions.	—
Alarms Last Min	The number of alarms the BACnet Server sent in the previous minute.	—
COVs Last Min	The number of COVs the BACnet Server sent in the previous minute.	—
Total Alarms	The total number of alarms sent since the BACnet Server service started.	—
Total COVs	The total number of COVs sent since the BACnet Server service started.	—

Troubleshooting

The following table is designed to help you resolve issues while configuring and running BACnet Server.

Problem

Cause

Resolution

TheStatus property for BACnet Server displays the following:

Configuration Error

The BACnet Server is not properly configured and is not communicating with the BACnet network.

Add a physical and a virtual connection to the Port table (BACnet Server Settings section).
If the BACnet driver and the BACnet Server are on the same BACnet network, make sure each has a different IP address.

TheStatus property for BACnet Server displays the following:

Unknown

The BACnet Server has not been configured.

Complete the steps in the BACnet Server Step-by-Step section.