Carrier i-Vu CIV-OR, Installation And Startup Manual

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Adjusting the i-Vu® Open Router driver properties
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Installation and Start-up Guide All rights reserved
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BACnet COV Throttling
Enable COV Throttling Under normal circumstances, COV Throttling should be enabled to prevent
excessive network traffic if an object's COV Increment is set too low. See
EXCEPTION below.
When enabled, if an object generates excessive COV broadcasts (5 updates in 3
seconds), the module driver automatically throttles the broadcasts to 1 per
second. Also, if the object's value updates excessively for 30 seconds, an alarm
is sent to the i-Vu® application listing all objects that are updating excessively. A
Return-to-normal alarm is sent only after all objects have stopped updating
excessively.
EXCEPTION In rare circumstances, such as process control, a subscribing object
may require COV updates more frequently than once per second. For these
situations, clear this checkbox, but make sure that your network can support the
increased traffic. You also need to disable the
Excessive COV alarms under the
driver's Common Alarms .
Device
On the Driver > Device page, you can change the following properties:
•
BACnet device object properties for the i-Vu® Open Router
•
i-Vu® Open Router communication
Configuration NOTE The three APDU fields refer to all networks over which the i-Vu® Open
Router communicates.
Max Masters and Max Info
Frames Max Masters - defines the highest MS/TP Master MAC address on the MS/TP
network.
For example, if there are 3 master nodes on an MS/TP network, and their MAC
addresses are 1, 8, and 16, then Max Masters would be set to 16 (since this is
the highest MS/TP MAC address on the network).
This property optimizes MS/TP network communications by preventing token
passes and “poll for master” requests to non -existent Master nodes.
In the above example, MAC address 16 knows to pass the token back to MAC
address 1, instead of counting up to MAC address 127. Each MS/TP master
node on the network must have their Max Masters set to this same value. The
default is 127.
Max Info Frames - defines the maximum number of responses that will be sent
when the i-Vu® Open Router receives the token. The default is 10 and should be
ideal for the majority of applications. In cases where the i-Vu® Open Router is
the target of many requests, this number could be increased as high as 100 or
200.