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Revision 0.07
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3.3.7.7 Rising Trip Point
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Figure 3-48 Rising Trip Point Entry
The default rising trip points are:
– Carbon Monoxide 100 ppm
– Nitrogen Dioxide 2.5 ppm
– Combustible 2,000 ppm
3.3.7.8 Falling Trip Point
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Figure 3-49 Falling Trip Point Entry
The default falling trip points are:
– Carbon Monoxide 50 ppm
– Nitrogen Dioxide 1.2 ppm
– Combustible 1,000 ppm
3.3.7.9 Multiple Sensor Mode
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Figure 3-50 Sensor Mode Selection
When multiple sensors are being monitored by a group the output decision can be based on either voting, as
shown here, or the average of all sensors in the group. Valid modes are:
– 1 Average
– 2 Voting
When the configuration is Average, the gas concentrations from all sensors in the group are averaged and if the
average is greater than or equal to the rising trip point the zone outputs(s) are activated. When the average is
less than or equal to the falling trip point the zone output(s) are de-activated. If the average is between the two
trip points, the outputs remain in there previous state.
When the configuration is Voting, the number of sensors in the group indicating a value greater than or equal to
the rising trip point is counted. If the count is greater than or equal to the quorum then the zone output(s) are
activated. If the count of sensors indicating less than or equal to the falling trip point is greater than or equal to
the quorum the zone output(s) are de-activated. Activating the output(s) is given priority if a group has an equal
number of sensors with gas readings ? the rising trip point and sensors with readings ? the falling trip point.
3.3.7.10 Multiple Sensor Quorum
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Figure 3-51 Quorum Entry
It is up to the installer to ensure that the quorum entry is appropriate for the configuration. Valid entries are one
to twelve, but a value greater than the number of sensors being monitored by the group, stops the group from
controlling the outputs.