
98
NFS2-640/E Programming Manual —
P/N 52742:L2 7/17/14
Intelligent Sensing Applications
Features
A sample sensitivity window for a laser detector:
Figure C.4 Sensitivity Levels for a FlashScan View
®
Laser Detector
C.2.5 Cooperative Multi-Detector Sensing
Cooperative Multi-Detector Sensing is the ability of a smoke detector to consider readings from
nearby detectors in making alarm or pre-alarm decisions. Each detector can include up to two other
detectors in its decision. Without statistical sacrifice in the ability to resist false alarms, Cooperative
Multi-Detector Sensing allows a detector to increase its sensitivity to actual smoke by a factor of
almost 2 to 1. Cooperative Multi-Detector Sensing also allows the combination of ionization with
photoelectric technology in reaching an alarm decision. The figure below shows a graph
representing Cooperative Multi-Detector Sensing:
Figure C.5 Cooperative Multi-Detector Sensing
2.0% Alarm Selection 9
1.5% Alarm Selection 8
1.0% Alarm Selection 7
0.5% Alarm Selection 6
0.2% Alarm Selection 5
0.1% Alarm Selection 4
0.05% Alarm Selection 3
0.03% Alarm Selection 2
0.02% Alarm Selection 1
1.5% Pre-Alarm 9
1.00% Pre-Alarm 8
0.7% Pre-Alarm 7
0.5% Pre-Alarm 6
0.2% Pre-Alarm 5
0.1% Pre-Alarm 4
0.05% Pre-Alarm 3
0.02% Pre-Alarm 2
Self Adjust 1
2.0%
2.1%
1.5%
1.0%
0.7%
0.5%
0.2%
0.1%
0.05%
SAMPLE
SENSITIVITY
WINDOW, laser detector
OBSCURAT
ION
(%
PER
FOOT
)
SMOKE OBSCU
R
ATION
Time (minutes)
Alarm
Combined
3 Sensors
Awa
cs5a
.wm
f