Beast DataSource

Overview

The Alarm System allow users to view and handle the alarms triggered by Process Variables (PVs) on front-end computers (IOCs). There are a set of dedicated applications (Alarm tree, table, and panel) which display alarms and alarm related information (like guidance). These applications also provide the ability to take a set of actions needed to effectively handle an alarm.

Refer to Help Contents -> CSS Applications -> Alarm System for a more detailed description of the beast alarm system

The beast alarm datasource provides a subsection of the alarm information and functionality. This makes it possible for user to access beast alarm information of any other cs-studio application. OPI screens can now embeded information about weather of not an alarm has been acknowledged, etc..

PV syntax

The standard prefix for the datasource is beast:// which can be omitted if configured as the default datasource.

'beast' pvs can be used to connect to any node or leaf from the alarm tree. The alarm tree represents the configured hierarchy of the alarm pv's, the hierarchy consists of

Area: Front end, DTL, CCL, SCL, Ring, ...
System: ICS, Cooling, Vacuum, RF, ...
Optionally sub-system: ICS/IOCs, RF/LLRF, RF/HPRF, ...
Alarm Trigger PVs on the final level.

You can create a beast channel for any Alarm Trigger PVs or for any Area, System, Subsystem.

  beast://alarm_trigger_pvName
  beast://complete_path_to_area
  beast://complete_path_to_system

Example1: Connecting to a alarm pv

Example2: Connecting to a subsystem defined in the alarm tree

Interpreting the beast datasource result

Each active alarm has several properties:

PV: name of the PV, Area, System.
AlarmSeverity:The severity of the PV remembered by alarm server. When the PV is configured to "latch", the alarm server remembers the highest alarm severity of the PV until it is manually acknowledged. Current severity of the PV might differ from alarm severity when the underlying alarm PV already recovered but the alarm server was configured to "latch" the alarm until operator acknowledgement.
CurrentSeverity: The current severity of the PV, like OK, MINOR, MAJOR or Invalid.
CurrentStatus: alarm status message like HIGH_ALARM or STATE_ALARM.
Active: true if severity indicates an active alarm, false for acknowledged or OK state.
AlarmState: Highest or latched alarm message. It would give more information and more human-readable than the raw PV name. It is also used for annunciation.
Value:
For a alarm PV it has the Value that triggered last status/severity update.
For a channel connected to a area/system.
Enable: true if the alarm/system/pv is enabled.
Type: node if the channel is connected to an area or system, leaf if the channel is connected to a pv.
Time: The time when the alarm happened.

Accessing individual fields

In addition of the table it is also possible to create a channel directly to some of the fields of the table

      beast://alarm_trigger_pvName.Enable

Returns a boolean value representing if the Alarm is enabled or disabled.

      beast://complete_path_to_area.Acknowledge

Returns a boolean value representing is the Alarm has been acknowledged.

true if severity indicates an acknowledged alarm (AlarmSeverity is *-ack'ed).

false for unacknowledged or OK state.

      beast://complete_path_to_system.AlarmSeverity

The severity of the PV remembered by alarm server. When the PV is configured to "latch", the alarm server remembers the highest alarm severity of the PV until it is manually acknowledged. Current severity of the PV might differ from alarm severity when the underlying alarm PV already recovered but the alarm server was configured to "latch" the alarm until operator acknowledgement.

      beast://complete_path_to_system.Active

Creates a Channel which represents if the alarm is active.

true if severity indicates an active alarm,

false for acknowledged or OK state.

      beast://complete_path_to_system.RawTable

Unlike the default table this table does not cast all values to String but rather creates a seperate column for each alarm attribute while preserving the type (i.e. the Enable/Active column returns Boolean values)

Writing

Writing to alarm pv's can be done by using one of the following key phrases.

ack: acknowledge this alarm pv or node.

unack: unacknowledge this alarm pv or node.

enable: enable this alarm pv or node.

disable: disenable this alarm pv or node.

Using beast datasource in BOY screens

The beast datasource can be used to embed beast alarm information into opi screens. The return value from the beast datasource can be easily displayed by using the VTable widget.
The example screen below was created with the beast datasource and the VTable widget.
Table 1. PV Formula = beast://LN-RF{MOD:3}Sum-Sts
Table 2. PV Formula = beast://NSLS2_OPR/Booster