Laser- based smoke detectors Lzr-1 7251

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

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

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

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

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.

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 --------“-------

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

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

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

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

Function of a laser group Example 1: Three laser detectors in the same fire zone   Fire zone X Laser group 01.001 01.002 01.003 Proportion value 0.5 0.8 0.2    Square rooting 0.5² 0.8² 0.2²    0.25 + 0.64 + 0.04 = 0.93 <1  No Alarm  

Function of a laser group Example 2: Four laser detectors in the same fire zone Fire zone X Laser group 01.007 01.012 01.053 01.094   Proportion value 0.5 0.8 0.2 0.3     Square rooting 0.5² 0.8² 0.2² 0.3² 0.25 + 0.64 + 0.04 + 0.09 = 1.02 >1  ALARM -- Fire alarm is shown from this address.  

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)

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. 01.001 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.

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

Smoke test 1 Fire Zone 1 00:00 START 00:55 ESA1 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 ESA1 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 ESA1 FIRE 01:15 VESDA FIRE 01:15 ESA1 2nd FIRE 01:20 ESA1 3rd FIRE 01:25 ESA1 4th FIRE