Banner SureCross DX80 Wireless Networks - Manual (Page 41)

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Banner Engineering Corp. • Minneapolis, MN U.S.A.
www.bannerengineering.com • Tel: 763.544.3164
SureCross Wireless Network
Product Manual
Message Codes
Node Link Failure
A Node Link Failure may be determined by the polling interval or the out-of-sync timing.
When a Node detects a communications failure with the Gateway and the ‘Node Link Failure’ flag is set, the output points are set to the user-
defined states and the inputs are frozen. When output points are set to their default states because of an error condition, only the Gateway can
clear the error condition and resume normal operation. The front panel buttons or the Gateway’s register I/O 15 clear error conditions.
Clearing a lost RF link error does not restore communications. Banner recommends determining and resolving the cause of the RF link error,
then allowing the system to auto-recover the lost communications.
In the sample system shown, the communication link between the Gateway and Node 1 has failed. Node 1 must have its ‘Node Link Failure’
flag set to allow its outputs to be set to the defined default state when it cannot communicate with the Gateway.
Polling Interval. The global ‘polling interval’ defines the time interval during which the Node should expect a polling request from the Gateway.
Out of Sync. An ‘out of sync’ condition is met when a Node fails to receive the Gateway’s beacon within a factory-set time period, about 10
seconds. Both the ‘out of sync’ and ‘polling interval’ conditions are used to detect a failure because the Node can remain in sync with the
Gateway but be unable to transmit data. If the Gateway drops out of the network, the Nodes will detect the ‘out of sync’ condition long before
the polling interval expires.