Page 349 - Programmable Logic Controllers, Fifth Edition - Mobile version

• Activation - Provides a secure, software-based sys-
detects alarm conditions and publishes event informa-
tem for activating Rockwell Software products. downloaded into a Logix controller. The controller
• Alarm and Events - Provides both server-based tion, which is routed through the system for display
and device-based process control alarm server. and logging.
Tag-based - Software-based tag servers monitor data
FactoryTalk alarms and events support the following
two types of alarm monitoring (Figure 14-50): tags for alarm conditions and publish event information
for display and logging. Tag-based alarm monitoring
Device-based - Pre-built alarm instructions that is supported by Logix 5000 controllers and SLC 500
are programmed in a Logix 5000 project and then controllers.

FactoryTalk Alarms and Using FactoryTalk FactoryTalk Alarms and Using FactoryTalk
Events services routes alarm 4 FactoryTalk 5 View SE Clients, Events services routes alarm 3 FactoryTalk 4 View SE Clients,
information to logs and to Alarms and Events operators interact information to logs and to Alarms and Events operators interact
Alarm and Event objects services with alarms (for Alarm and Event objects services with alarms (for
embedded in graphic example, embedded in graphic example,
displays in FactoryTalk View acknowledge, displays in FactoryTalk View acknowledge,
Device server notifies 3 suppress) from suppress) from
FactoryTalk Alarms and graphic displays Tag Alarm and Event Server 2 graphic displays
Events services of alarm polls controller to monitor
state changes Alarm and Event alarms and then notifies
History log users of alarm conditions Alarm and Event
History log
2 Controller detects alarm
conditions and notifies device
server of changes in alarm states
1
1
Logic in a controller is
RSLogix 5000 alarm programmed to detect
instructions are programmed problems and latch fault
and then downloaded into conditions in controller tags
the controller or addresses
(a) Device-based alarms (b) Tag-based alarms
Figure 14-50 FactoryTalk alarm monitoring.
Source: Images Courtesy of Rockwell Automation, Inc.

330 Chapter 14 Process Control, Network Systems, and SCADA

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