Alarm classes and groups

An alert class gives an alarm its priority and its default acknowledge mode. An alarm group collects alarms by rules, for example all alarms of an area or all alarms from high priority up, so that a screen can show and acknowledge them together. Both are set up in the Alarms work area of the configuration editor (Alt+5).

Before you begin

• For the area rule on this page, the areas plant/pumps and plant/tanks exist; see Alarm areas.

Steps

1. Add alert classes

Open Alarms · Classes and the Alarm classes tab. Click New row, type the Name and click Add. Then select a cell of the row, press F2 and fill in Priority. Here the classes are critical 90, high 70, medium 40 and low 10. Apply the change.

Column	Values
Name	The class name, shown in the alarm definitions
Priority	0–255; a larger number is more urgent. 80 and above is Critical, 60–79 High, 20–59 Medium and below 20 Low
Color	A color for the class
Ack mode	none, came, pair or deletes (see Acknowledge modes); empty is came
Common confirm	On or off

A class is chosen for each alarm level in Alert class of the signal's Alarm tab (see Define alarms). An acknowledge mode set on the alarm itself overrides the class. When a numeric signal's levels have different classes, the alarm takes the most urgent one; a level without its own class uses the class of the alarm.

2. Add alarm groups

Open Alarm groups. Click New row, fill in Name, Parent and Description and click Add. Here the group station contains the sub-group pumps. Apply the change.

A group name may contain letters, digits and _, with up to 64 characters. Active is on for a new group; a group that is not active is ignored.

3. Add group rules

Open Group rules. Click New row, choose the Group, the Field and the operator Op, type the Value and click Add. Here pumps collects the alarms of the area plant/pumps and its sub-areas, and station every alarm from High priority up. Apply the change.

Field	Compares
area	The area path of the signal
path	The signal path
priority	The priority: low, medium, high, critical or 0–3
alarm_class	The name of the alert class
signal_type	The signal type of the signal
attr_t01–attr_t16, attr_b01–attr_b16	The text and on/off attributes of the signal

Op	Matches when the value
eq, ne	is, or is not, the given value
in	is one of a comma-separated list
prefix, contains	starts with, or contains, the given text
range	lies between Value and Value2, both included
gt, ge, lt, le	is greater than, at least, less than or at most the given number

• Texts are compared without regard to case. When both sides are numbers, they are compared as numbers.
• All rules of a group must match. To collect alarms that match one rule or another, make a sub-group for each rule: a group also contains the alarms of its sub-groups.
• A group without rules contains only the alarms of its sub-groups.
• An empty attribute matches only ne.

Acknowledge a group

Put an Alarm group object on a screen and turn on Acknowledge group button. On the runtime screen the button acknowledges every unacknowledged alarm of the group with one click; it needs the right to acknowledge alarms. See Put alarm objects on a screen.

Alarm counters

YTCC keeps counter signals for the whole project, for each area and for each group. They are read-only system signals, updated within a quarter of a second, and can be bound on screens and used in scripts like any signal.

Scope	Signals
Project	Alarms.Summary.<counter>
Area	Alarms.Areas.<area>.<counter>; a sub-area under .Sub.<name>
Group	Alarms.Groups.<group>.<counter>; a sub-group under .Sub.<name>

Counter	Counts
Active	Alarms that have come and not gone
Unacked	Alarms awaiting acknowledgement, active or gone
Acked	Active acknowledged alarms
ReturnedUnacked	Gone alarms awaiting acknowledgement
Open	Active plus ReturnedUnacked
Shelved	Shelved alarms
Critical, High, Medium, Low	Active alarms of each priority
HighestPriority	The highest priority among the active alarms: 0 none, 1 low, 2 medium, 3 high, 4 critical
HasUnacked	On while an alarm awaits acknowledgement

Shelved alarms count only in Shelved; alarms that are out of service or suppressed are not counted. In the signal names, letters outside a–z are converted, for example Ü to u, and other characters become _.

Good to know

• priority in a group rule uses 0–3 (0 low), while the counter HighestPriority uses 0–4 (0 none).
• Changes to groups and rules reach the counters at the latest one minute after they are applied.