Six flame detectors have already been added to the project so that coverage results have already been calculated.
Click the Show Coverage Results icon on the toolbar, change the Show Results By to Subzone so that the results for each individual sub-zone is shown, as in Figure 9 below.
Tutorial 5 - Figure 09 - Coverage results displayed by sub-zone regions
Now change the Show Results By to Risk Grade. Here we see the coverage result for each risk grade in the zones of the project. The Default risk grade is automatically hidden from the coverage results but this can be changed in its properties panel.
Tutorial 5 - Figure 10 - Coverage results for risk grades
The risk grade coverage is calculated as a summation of all the zone and sub-zone coverage volumes for each grade in the project. For example, Sub-Zone 04 - Compressors and Sub-Zone 05 Valve Set both have been assigned as Grade A. The total external volume of the two sub-zones is added up to form the 'total volume' of the Grade A region. Percent coverage is then based on how many detectors can see the 'total volume' of the Grade A region.
Tutorial 5 - Figure 11 - description of risk grade coverage calculation
The same calculation is done for the other coverage levels (0ooN, 2ooN, etc).
As Grade B was only assigned to Sub-Zone 03 - Valves and Pumps the sub-zone coverage will match the Grade B coverage.
Risk grades can be renamed via their properties panel, shown below, to better classify equipment and also provide grouped coverage results for each type of equipment in the project. Click off the panel to verify a newly entered name.
Tutorial 5 - Figure 12 - Indication of where to change a risk grade name
The names of the risk grades will be what is reported by the coverage results window, seen below.
Tutorial 5 - Figure 13 - Updated Coverage Results window