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Mass Notification System Introduction
14.1
Virtual Zones
A virtual zone is a zone that is not associated with any physical devices but instead monitors
inputs across groups and activates outputs across groups using advanced logic.
Even though the MNS has a fire monitoring component, it cannot control fire devices.
Governing bodies such as UL/ULC require that MNS and fire control systems be grouped
separately in the software. The input and output devices for fire and MNS must be in different
zones and these zones must be in different groups. Since an input zone cannot activate
outputs in a different group, the MNS input zones will not activate fire output signals and fire
input zones will not activate MNS output signals.
However, sometimes inputs from one group require the use of hardware present in a different
group. For example, the fire group may have inputs that require the use of amplifiers in the
MNS panel. You can use virtual zones to make inputs activate outputs across groups.
Chapter 6 outlines how to use advanced logic with virtual zones.
14.1.1
Conflicts with virtual zones
Sometimes conflicts can occur. For example, two inputs may try to activate the same output
simultaneously. To prevent this, you can give priority to either MNS or fire.
For example, if MNS has a higher priority and a fire input activates:
1. The fire output remains active until an MNS input activates.
2. When an MNS input activates, the MNS output takes over and silences the fire output.
3. When the MNS output is finished, the fire output resumes.
Figure 68 Virtual Zone Priorities
Fire Input
- Manual Stations
- Switches
- Detectors
MNS Input
- Manual Stations
- Switches
- Other
Fire Zone
MNS Zone
Advanced Logic Equations
Fire Virtual Zone
MNS Virtual Zone
Output Hardware
- Speakers
- Horns
- Strobes
Output Hardware
- Speakers
- Horns
- Strobes
FIRE GROUP PRIORITY LEVEL 1
MNS GROUP PRIORITY LEVEL 2
