Time synchronization properties

An AX-3.5 or later BacnetNetwork’s LocalDevice component has a collection of “Time synchronization server” properties, formerly available only in the LocalDevice of a BACnet Supervisor station (BacnetWsNetwork). The LocalDevice in a BACnet AWS Supervisor (BacnetAwsNetwork) or BACnet OWS Supervisor (BacnetOwsNetwork) also uses this same collection of properties.

These properties are at the bottom of the network’s LocalDevice property sheet (Figure 10).

Figure 10. Time Synchronization properties in BacnetNetwork LocalDevice’s property sheet

Configuration allows periodic BACnet time synchronization messages to be sent from the station to all defined time synchronization recipients (devices), or to UTC time synchronization recipients (devices), at the interval specified in the properties. The following properties are in this collection:

Time Synchronization Recipients

Contains the list of recipients for periodic Time Synchronization messages. You can add and remove entries to this list using the right-click addElement and removeElement actions. Entries in this list are BacnetRecipients. They can be either a Device Object Identifier, or a BACnet Address. See Figure 11 for an example of the popup dialog from invoking the addElement action.

Figure 11. Adding time synchronization recipient with right-click “addElement” action

As shown in Figure 11 above, the default addElement popup dialog is for Device object instance number (click on the small drop-down control, and then drag the popup corner out to access the instance number field.) Edit from the default -1 to the device’s unique Device instance number.

Or after resizing, click the drop-down control beside “Device” and change to “Address.” This changes the addElement popup dialog to have different fields, as shown in Figure 12 below.

Figure 12. Dialog to specify time synchronization recipient by Address instead of Device instance number

In this case you must know the BACnet device’s network number, MAC address, and MAC address style (choices are Ethernet, IP, MSTP/Other, and Unknown).
Time Synchronization Interval

Configures how frequently Niagara will send the time synchronization messages. The default value is 24 hours.
Align Interval

Specifies if the periodic time synchronization messages should be aligned to the beginning of the next interval. For example, if Time Synchronization Interval is exactly 24 hours and Align Interval is true, then the time synchronization messages will be sent out exactly at the beginning of the day, at 12:00 midnight.
Interval Offset

Specifies an offset from the beginning of the interval at which to send the periodic time synchronization messages. If Align Interval is false, this property is ignored.
Utc Time Synchronization Recipients

Contains the list of recipients for periodic UTC Time Synchronization messages. Works the same as the Time Synchronization Recipients property, where you can add and remove entries to this list using the addElement and removeElement actions (see Figure 11 and Figure 12). The entries in this list are BacnetRecipients. They can be either a Device Object Identifier, or a BACnet Address.