Querying

To make an alarm query, three simple options need to be input in the Alarm Query Bar:

1. Carriageway:
2. Rule Type:
   1. Debris
   2. Enforcement
   3. ERA
   4. Person
   5. Queue
   6. Reversing
   7. Slow
   8. Stopped
3. Time Period:
   1. 24 hours
   2. 48 hours
   3. 72 hours

The results are automatically calculated and will be presented in the four graphs below; a Rules bar graph, an Alarm Count (per Sections) line graph, a Top Alarm Sections pie chart and an Alarms by Time line graph. In the example below, the alarm query has been for Debris alarms in the 'School Road' carriageway over the last 24 hours:

The graphs indicate:

1.  There have been 300 Debris alarms in the past 24 hours.
2.  Of those alarms, Section 5 had the most - 114.
3.  There was a spike in the frequency of Debris alarms at around 04:30 am.

Select the  symbol in order to export and save Alarm Query data. 

Rules

The Rules bar graph indicates the volume of alarms separated by Rule Type. The default display for the Rules graph on the Alarm Dashboard presents all Rule Type alarms; a query must be made to display an individual rule's alarms. The exact value represented by the bars can be identified by hovering the cursor over a bar:

It is possible to adjust the alarm results displayed in the Sections and Alarms by Time line graphs by 'deselecting' rules, through clicking on their bars. This will remove that rule's alarm data from the accumulated data displayed in the two line graphs, and could be useful if a scale is skewed by a particular rule's alarm count being far higher than any other. A 'deselected' rule is indicated by changing from opaque to translucent magenta. The example below is the 'deselection' of the Debris rule, and therefore the Sections and Alarms by Time line graphs only display Person and Slow rule alarm data:

Sections

There are two Sections graphs; Alarm Count and Top Alarm Sections. The Alarm Count line graph by default depicts the accumulated alarms per section of all Rule Types. The exact number of alarms in each section can be identified by hovering the cursor over the points of the line graph:

The Top Alarm Sections pie chart breaks down the Alarm Count in each section into their comparative proportional values. It also lists the sections into descending order of Alarm Count. Hovering the cursor over individual sectors in the pie chart will highlight which section they represent in the list below:

Alarms by Time

There are two Alarms by Time line-graphs: Section Alarms and System Alarms. Each represents the spread of alarm frequency over time. The default time period will be 24 hours, but a period of up to 72 hours can be selected to be represented in an Alarm Query. The numbering alarms per specific hour can be identified by hovering the cursor over the points of the line graph:

System Alarms represents the alarms caused by any system fault or failure over the time period selected (the default will be 24 hours). In the example below, a perfect Witness ClearWay™ system has no errors and therefore no alarms:

Related information

• Page:
  Live (Witness 4.0)