Issue
BACnet COV subscription system
Product Line
EcoStruxure Building Operation
Environment
- BACnet Settings
- COV subscriptions
- v1.7 and earlier
Cause
A site will have a problem with the amount of traffic because of misconfigured COV Increments. The problem is that Building Operation, the ES and AS resubscribes to values every 10 seconds and one by one.
So for example:
hh:mm:ss 00:00:00 Value1 00:00:10 Value2 00:00:20 Value3 00:00:30 Value4 ... 05:00:00 Value1800
If you have more than 1800 subscriptions the ES or AS is not able to do all subscriptions in 5 hours. 5 hours is used because Building Operation subscribes to the values with a lifetime of 5 hours.
Resolution
BACnet COV subscription system is not influenced by the requested transfer rate in the edit bindings system (Subscriptions using BACnet). That is used in the case where the external device does not support COV, and read-property must be used instead.
The design in 1.4 and 1.5 simply did not anticipate such large numbers of COV subscriptions.
Workaround:
- 1.Exit Workstation
- 2. Stop the Enterprise Server
- Edit using notepad the server.properties file located in "C:\Program Files\Schneider Electric StruxureWare\Building Operation 1.x\Enterprise Server\etc\
- Find at the bottom:
# Set GenericConsume communication defaults - Add the two following lines:
NspServer.BACnetPlugIn.COVSubscriptionLifetime entry = 28800
NspServer.BACnetPlugIn.COVTimerPeriod entry = 5 - Save your changes and close the server.properties file.
This changes the default values from 5 hours to 8 hours and 10 seconds to 5 seconds.
NOTE From version 1.8 the BACnet Interface manager (/Server 1/System/Interface Manager/BACnet) provides access to these settings (COV subscription lifetime (default 8 hours) and Server COV renew rate(default 5 seconds)) The settings will be controlled via the Enterprise Server if connected.
