1. Laser- based smoke detectors
Lzr-1
7251

2. LZR-1 Detector Chamber Laser Diode
Laser produces a brighter, more concentrated beam of light
More signal is achieved due to the more concentrated light
Smaller particles can be detected due to the brighter light
Laser Diode

3. Laser Detector Benefits
Standard optical smoke detector princible
Smoke Sensor
(Photodiode)
Focussed beam
improves settled dust performance
improves airborne dust performance
Light Source
(LED)

4. Applications suitable for LZR-1
High value property, clean environments
Telecommunications switching rooms
Computer Rooms
Electrical equipment rooms
Museums, galleries etc..
Avoid
cigarette smoke, dust, steam, exhaust fumes, textile fibres

5. Detector spacing / coverage
Low Airflow ( < 10 air changes per hour)
40m2 per detector (3.5m radius)
High Airflow ( > 10 air changes per hour)
25m2 per detector (2.8m radius)
Extra detectors may be placed
at inlets to air conditioning systems
areas of high air movement
inside cabinets
floor and ceiling voids

6. Function of LZR-1 laser detector and a laser group in Esa1 system
PW4 analogue value of the new detector is between 100 … 500s.
The Basic Environment Level (B.E.L) in panel memory is updated every 5th minute.
Time constant is 21h when the value is rising (up to 65% of the new value) and 25min when it’s decreasing (65% of new value).
Fire- and pre-alarm levels can be set between B.E.L + 60 … 2000s.
Saturation value of panel’s memory is updated once during daytime between
10.00 … 16.00, and it can be between 2600 … 4000s.
Time constant for saturation is 16 days (65% of new value).
Fire level or pre-alarm level are in any case 100s under the saturation value, no matter what the configured value is.
Maintenance warning level is fixed to 1200s.

7. Configuration levels vs. analogue values
Level 1 = 60s over B.E.L
Level 2 = 280s “
Level 3 = 490s “
Level 4 = 710s “
Level 5 = 920s “
Level 6 = 1140s “ (default value for pre alarm)
Level 7 = 1350s “ (default value for fire alarm)
Level 8 = 1570s “
Level 9 = 1780s “
Level 10 = 2000s “

8. Signal processing Example 1 Fire alarm set to level L1
-Panel is filtering interferences from the signal of detectors, and will
proportionate the signal between 0 and 1, so that B.E.L is 0 and alarm value is 1.
Example 1 Fire alarm set to level L1
360s Fire alarm level = B.E.L + 60s (level 1)
330s Measuring value 330s  proportion value is 0.5
300s B.E.L 300s

9. Signal processing Example 2 Fire alarm set to level L7
1350s Fire alarm level = B.E.L s (level 7)
330s Measuring value 330s  Proportion value is 0.022
300s B.E.L 300s

10. Function of a laser group
Laser detectors in the same fire zone will automatically form a laser group
There is no need for configuration.
Proportion values of all detectors in same laser group are squared and added together. 
If the sum value is 1 or more, it will activate the alarm, which is shown from the address where the proportion value is highest.
If the value of a single detector is 1 or more, it will activate the alarm.  
The function is the same with Fire-alarm and Pre-alarm

11. Grouping Algorithm
Signal from detectors in close proximity is summed using a ‘mean square’ algorithm - 2= A 2 + B 2 + C 2
Grouping of detectors gives a higher effective sensitivity with less risk of false alarms
For best performance always use more than one detector in any area

12. Function of a laser group
Example 1: Three laser detectors in the same fire zone
Fire zone X
Laser group
Proportion value
  
Square rooting ² ² ²
  
= <1  No Alarm

13. Function of a laser group
Example 2: Four laser detectors in the same fire zone
Fire zone X
Laser group
Proportion value
   
Square rooting ² ² ² ²
= >1  ALARM
-- Fire alarm is shown from this address.

14. Selection of Sensitivity
High Sensitivity Pre-Alarm
Alarm sensitivity from 0.01% / ft to 1.0%/ft
Set Pre-alarm sensitivity just high enough to meet ‘hot-wire’ test
Monitor system for three months
Use lower sensitivity alarm (> 1.63%/m)

15. Analyzing of LZR-1 signals
Analogue values of LZR-1 detector can be seen on access level three
There are six PW4 values at one window for one detector
ZONE 0001 ADDR ENABLED
LASER SENSOR A2 S28 C204 M186 P 0 F 0
A = Basic Enviroment Level (BEL), from which two least significant digits are removed.
In this case A2 can be between 200s … 299s.
S = Saturation value, from which the two least significant digits are removed.
In this case S28 can be between 2800s … 2899s.
C = Last value from detector without filtering.
 M = Value after filtering (lowest of the last tree readings).
 P = % of Pre alarm level.
F = % of Fire alarm level.

16. Test: Aspirating system vs. ESA1+LZR-1
ASPIRATING TUBE
AND DETECTORS
VESDA / AIR-SENSE
CENTRAL UNIT
DETAILS
POWER ELECTRONIC CABINETS

17. Smoke test 1 Fire Zone 1
00:00 START
00:55 ESA FIRE
01:20 ESA1 2nd FIRE
01:25 ESA1 3rd FIRE
01:40 VESDA FIRE
01:45 ESA1 4th FIRE
Smoke test 2 Fire Zone 1
00:00 START
00:45 VESDA WARNING
00:55 ESA FIRE
01:10 VESDA FIRE
01:15 ESA1 2nd FIRE
01:20 ESA 3rd FIRE
01:25 ESA 4th FIRE
Smoke test 1 Fire Zone 2
00:00 START
00:50 VESDA WARNING
01:05 ESA FIRE
01:15 VESDA FIRE
01:15 ESA1 2nd FIRE
01:20 ESA1 3rd FIRE
01:25 ESA1 4th FIRE