Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
A P P L I C A T I O N S G U I D EFiltrex ®A Smoke Detector forDifficult EnvironmentsContentsSection 1 Product Overview ..........................................................................................................................................................2Section 2Operating Principles......................................................................................................................................................2Section 3 Filtrex ® Proves Itself ......................................................................................................................................................3Section 4 Applications ....................................................................................................................................................................3Section 5Application and Placement Considerations..............................................................................................................4Section 6Installation Considerations...........................................................................................................................................5Section 7Specifications.................................................................................................................................................................5BenefitsFiltrex goes to the worst places. Made for some of most difficult interiorenvironments on earth, it holds its own against dust, insects and will evenwithstand occasional water spray. This specially designed, patented smokedetector filters airborne particulate so it can concentrate on sensing smoke.Filtrex is fast. Its early response time provides early detection — well beforeslower-responding thermal detectors — thereby minimizing property loss.It doesn’t fool with fire. Filtrex virtually eliminates false alarms — minimizingbusiness interruption.Filtrex installs easily into existing analog-intelligent systems.1
F I L T R E X ® : A S M O K E D E T E C T O R F O R D I F F I C U L T E N V I R O N M E N T SSection 1Product OverviewThe first difficult environmentsmoke detectorIt’s well known that smokedetectors just don’t work in certain places. Dirty, dustyplaces like paper mills. Lumber mills. Cotton and textilemills. Dry chemical processing plants. Horse stables andother climate controlled animal holding areas.Until now, it was next to impossible to achieve true earlywarning of smoke in these dusty, dirty environments. Nosmoke detector could stand up to the punishment of dust.Anyone bold enough to try a photoelectric smoke detectorin such a place would report the same experience — frequentfalse alarms or frequent maintenance.Until now, specifiers could only choose between thermal,flame detectors, thermal wire or beam detectors. Some ofthese alternatives, such as flame detectors, could be effective,but are expensive and maintenance-intensive. Others,such as thermal detectors, could be slow to react — and inthe fire detection business, too slow can be too late.Although these technologies can save lives, they may notrespond early enough to prevent property damage. Andprolonged extinguishing by water sprinklers or misters canactually increase property damage.Filtrex entirely changes this picture. Using a high-densityfilter and air intake system, Filtrex removes airborne matterbefore it reaches the smoke sensor. Dust, insects, waterspray — Filtrex shuts them all out.And that frees the sensor to do its job: sense smoke.The results of this technology?• Demonstrably superior performance.•True early warning.•Rapid response without false alarms.• Straightforward installation into existing systems.•Low maintenance.Filtrex is also fully supervised. Internal circuitry can detecta clogged filter or fan failure.While Filtrex is ideal for some of the most dusty and dirtyplaces on earth, it is not intended for exterior use, nor is itrecommended for extremely hot, humid, corrosive, hazardous,intrinsically safe or explosive environments.Section 2OperatingPrinciplesFiltrex removes foreign particulate— such as dust andwater spray — while allowingsmoke to arrive at thesensor.Photoelectric smoke detectors provide advanced warningof impending fire without requiring heat to alarm.2. Smoke SensorAir and SmokeHowever, because these smoke detectors work on a lightscatteringprinciple, any particulate that enters the sensingchamber can lead the sensor to believe it is detectingsmoke. The result: a possible false alarm.Filtrex is a specially-enclosed intelligent photoelectricsmoke detector that provides the ability to operate normallyin environments that would otherwise cause falsealarms. The sealed enclosure contains two high-density airfilters that capture dust and water spray while allowingsmoke to pass through to the sensor. A small fan draws-infiltered air samples, cycled on and off to increase its lifeand reduce current draw.Filtrex draws air (1.) through two high-density filters. Onefilter is field-cleanable; the other is permanent to protectthe sensing chamber. A fan, cycled to increase lifeexpectancy and reduce current draw, pulls the air throughthe fine filters and past the sensing chamber (2). Air is thenexhausted (3.) through the chamber and back out thecover. A standard photo sensor is used as the sensingdevice. Gaskets provide additional dust protection.FanFilters3. ExhaustCycled SamplingAir is sampled every 35 seconds for five seconds. Air flowis checked every four hours for 15 seconds. Two high densityfilters remove particulate.Continuous ProtectionSmoke is detectable while water spray or dust is present.Full SupervisionIf a filter clogs, the panel is alerted and the device is takenoff-line. Power-up is automatic when the dirty filter isreplaced.1. Air, Smoke, Dustor Water Mist2
S Y S T E M S E N S O RSection 3Filtrex ®Proves ItselfSmoldering Fire TestIn this test, a UL smoldering fire (see UL standard 268 formore details about this fire) was performed in which 10small pieces of wood were placed on a hot plate. At timezero the hot plate was at room temperature. It was slowlyramped to a temperature of around 500ºF. Smoke begangenerating around the 20 minute mark. Filtrex, in this test,alarmed about 20 minutes after the first smoke was generated.This particular fire would not generate enough heatto alarm a heat detector until a flame-over conditionoccurred and sufficient heat was generated. As you can seehere, Filtrex may provide an early warning.Detector SignalTimeFiltrex responds to smoldering fires while heat detectors may not.FiltrexAlarm ThresholdHeat DetectorAirborne Dust TestThis graph shows the results of two separate trials testingthe performance of a standard photoelectric smoke detectoragainst Filtrex in a dusty environment. In each test, thesignals from the detectors are monitored while they areexposed to a predetermined amount of dust. In each trial,the standard photoelectric smoke detector reaches thealarm threshold, while Filtrex stays safely below.Maximum Detector SignalAlarm ThresholdFiltrexStandard PhotoelectricFiltrexStandard PhotoelectricTrial 1: 0.12 grams of dustTrial 2: 0.24 grams of dustSection 4ApplicationsNote to specifiers: check that the specified product temperatureand humidity conditions are met.Potential Applications•Paper and lumber mills• Cotton and textile mills• Dry chemical processing plants• Duct Installations•Food processing plants•Packaging areas (corrugated dust)• Laundry rooms•Wash-down and hose-down areas• Animal holding areas (zoos, stables, barns)• Motion picture studios• Subway tunnelsApplications to Avoid• Explosive conditions• Out-of-range temperature and humidity• Hazardous environments• Outdoor or marine installations• Unheated animal barns3
F I L T R E X ® : A S M O K E D E T E C T O R F O R D I F F I C U L T E N V I R O N M E N T SSection 5Application andPlacementConsiderationsAlthough Filtrex isdesigned to withstand verydirty environments, it doeshave some limitations.During our extensive fieldsite testing, we gained valuable experience on how to bestapply the product. Performance feedback indicates thatFiltrex provides superior detection in difficult environments,as there have not been any reported false alarms.Here are some factors to consider when evaluating potentialapplications.Temperature ConsiderationsImportantly, Filtrex is not an outdoor product. Observetemperature range when specifying product. The UL specifiedtemperature range is 32 degrees to 120 degrees F (0degrees to 49 degrees C) and relative humidity is10%–93% noncondensing.Water SprayFiltrex has also been designed to withstand periodic contactwith water spray directed at the housing. Filtrex filtershave a special coating that prevents water from passingthrough or clogging the filter; water beads on the filter andfalls off. A potential application could be a wash-downarea where there is periodic over-spray that contacts thedetector. There should be adequate time between watercontact for the unit to dry. Filtrex has not been designed forcontinuous water contact nor has it been designed to withstanda forceful direct spray. Also, damage may occur ifwater is allowed to enter from the back of the base wherethe power and communication wires enter.Particle size and filter issuesThe two high-density filters that remove airborne particulatehave a pore size of 32 microns. This opening size hasbeen carefully chosen through extensive testing to balancebetween keeping dirt particles out while still allowing adequatesmoke entry. So, depending on the particular environment,there is a possibility that a small amount of particleswill enter the chamber. In this case, you may experiencea low level detector response (analog output fromFiltrex shows an increase in signal). But, this increasetends to be well below alarm threshold and, compared toan open area smoke detector in the same environment, isdrastically lower. Tests also show that over time, the particlesdo not tend to build-up, but rather are exhausted fromthe chamber. With the majority of industrial conditions,there should not be an issue, but consideration should begiven to the expected particle size distribution of the dustor dirt found in a given environment.The rate of filter clogging on Filtrex will vary for each individualapplication. Factors include density, size and structure(fiber, spherical, etc.) of the particles, duration and frequencyof high dust conditions, and "stickiness" of the particles(will they adhere to the filter or lay on the surface).We have seen conditions where the filter could last for severalyears and conditions where filter life was much shorter.*Again, each application will be different and thus, willhave varying filter life. If the filter does clog, simplyremove the cover/filter assembly and replace with a newone (replacement cover/filters are available). Note: As airflowis reduced due to clogging, Filtrex cuts power andcauses a trouble signal at the fire alarm control panel.*Interestingly, we found that in some especially toughareas, changing the filter even on a monthly basis is not toohigh a price for some customers to pay for detection theyhave never been able to get before.PlacementFor placement and spacing purposes, Filtrex is a spot typesmoke detector. NFPA 72 guidelines for open area smokedetectors should be observed. A few other common senserules will allow the product to work as specified:• Do not install Filtrex at steam outlets. Steam particlesare very small and may pass through the filters, causingfalse alarms.•To extend filter life, do not install Filtrex in the directpath of extreme amounts of dust. Although falsealarms should not be a problem, carefully placingunits can add substantial life to filters.After a fireFilters should always be replaced after any fire condition toensure that proper airflow is maintained. Smoke fromactual fires will have a tendency to stick to the filters andreduce airflow.Applications SupportCall your fire system supplier or System Sensor with anyquestions.4
S Y S T E M S E N S O RSection 6InstallationConsiderationsInstallation of the Filtrexsystem is essentially thesame as installing standardintelligent photoelectricsmoke detectors, although the mounting base is modifiedfor additional electrical connections.RemoteAnnunciatorRA400Z– +1(+) 2(–) 3(RA) 4(S)AUX– AUX+1(+) 2(–) 3(RA) 4(S)AUX– AUX++ –+–Control PanelAuxiliaryPowerSupplySection 7SpecificationsFiltrex Smoke Detector for Difficult EnvironmentsSize 3.5 in. (8.9 cm) H x 4.0 in. (10.2 cm) dia.Weight 7.3 oz. (207 g)Detector Input Voltage 15 – 32 VDCDetector Current Draw 250 µA max. @ 24 VDC (without communication)360 µA max. @ 24 VDC (one communication every 5 sec. with LED enabled)Auxiliary Power Supply Input Voltage 15 – 30 VDC (filtered)Auxiliary Power Supply Current Draw Average current: 27 mA max.Peak current: 123 mA max.Operating Temperature Range 0° to 49°C (32° to 120°F)Relative Humidity 10% – 93% noncondensingRated Air Velocity 0 – 4000 ft./min. (0 – 20.3 m/s)5
Distribuição: <strong>Alarmes</strong> <strong>Tucano</strong> LtdaR. Des. Antônio de Paula, 3577 - Curitiba - PrFone/fax: (41) 326-2867 - Cep: 81720-280tucano@tucanobrasil.com.brwww.tucanobrasil.com.br