Rockwell Automation FactoryTalk Historian SE 3.0 UniInt Interface User Guide - Manual (Page 84)

UniInt Failover Scheme
78
Historian Tag Value Description
Heartbeat 2 Input Tag
Exdesc:
[UFO_HEARTBEAT:2]
Updated by the Interface
on IF-Node2
Values range between 0
and 31
The Heartbeat 2 Input Tag must be configured
as a valid input Historian tag for the interface
and it must be configured to read the Heartbeat
2 Point on the Data Source.
Consult the Interface User‟s manual for a
description of configuring input tags.
The exdesc must start with the case sensitive
string: [UFO_HEARTBEAT:2]
The value following the colon (:) must be the
Failover ID for the interface running on IF-
Node2. In this example, the Failover ID is 2.
Heartbeat 2 Output Tag
Exdesc:
[UFO_HEARTBEAT:2]
Updated by the Interface
on IF-Node2
Values range between 0
and 31
The Heartbeat 2 Output Tag must be
configured as a valid output Historian tag for
the interface and it must be configured to write
to the Heartbeat 2 Point on the Data Source.
Consult the Interface User‟s manual for a
description of configuring output tags.
The exdesc must start with the case sensitive
string: [UFO_HEARTBEAT:2]
The value following the colon (:) must be the
Failover ID for the interface running on IF-
Node2. In this example, the Failover ID is 2.
State 1 Tag
Exdesc:
[UFO_STATE:1]
Normally updated by the
Interface on IF-Node1.
May be updated by the
interface on IF-Node2 if
IF-Node1 is unable to
update the tag
Values range between 0
and 5, see description.
The failover state tags are optional and do not
require a point on the Data Source. The value
of the state tag can be written to the Data
Source by configuring a normal interface output
tag and setting the SourceTag attribute to the
failover state tag.
The failover state tags were designed to be
digital tag assigned to a digital state set with
the value values.
0 = Off: The interface has been shut down.
1 = Backup No Data Source: The interface is
running but is unable to communicate to the
data source.
2 = Backup No Historian Connection: The
interface is running and connected to the data
source but has lost its communication to the
Historian Server.
3 = Backup: The interface is running and
collecting data normally and is ready to take
over as primary if the other copy shuts down or
experiences problems.
4 = Transition: The interface will be in this state
for only a short period of time. The transition
period is designed to prevent thrashing where
both copies attempt to assume the role of the
primary interface.
5 = Primary: The interface is running, collecting
data and sending the data to Historian.