Fire & Security Products Siemens Flame Detector a highlight in detection technology.
Keeping a very close eye on nature. Flames are a fascinating - but at the same time threatening - natural phenomenon. The magic of flames has captivated not only artists, but also our research and development staff. Flames are a visible distinguishing feature of fire. Siemens has specialized for decades in the use of electronic sensors to detect fire. Let s take the Siemens flame detector as an example to illustrate the fascinating methods modern fire engineering employs to do this. Flames are like everything else in nature - so different and yet so similar to each other. But just what are their unmistakable features? Imagine the flame of a candle or a cigarette lighter, or the sea of flames in a heap of burning wood. So different from each other and yet the same. Now think of the lighter flame and how it radiates light regularly when it is undisturbed Fire phenomena by wind. However, as soon as you blow into it, it changes its appearance. It becomes unsteady and starts to flicker. Now try to describe the differences. It s not so easy! Yet it is precisely this description which is crucial for distinguishing a flame from a deceptively similar phenomenon. There are lots of these: reflecting surfaces intermittently reflected sunlight glittering objects rippling pools of water, etc. A flame detector must not actuate an alarm in these cases! Deceptive phenomena Pattern recognition - a principle of nature 2
A simple description of complex phenomena. Flame or no flame? - In order to obtain a precise answer to this question from an electronic detector, you have to apply soundly based, scientific methods. This is because flames appear in endless variety. Filtering the relevant information from a multitude of data Then comes the model of the flickering flame Let s illustrate the problems involved with another example. From a file of millions of fingerprints you are looking for exactly those prints which clearly identify one specific person. To do so you need either an army of staff and no time limits - or you find another way. More of that later. You will find the answer described on the next page. Siemens has made an intensive detailed study of the phenomenon of flame in its basic research, and in the process has identified typical characteristics featuring model behaviour. The model creates a relationship between the size of the fire and the flicker frequency of the flame. The model assumptions are closely related to the real-life situation and also take into account, for example, air currents acting on the flame. The first thing that has to be understood is: What is a flame? A flame is a physical phenomenon. Its description as a dynamic process involves a combination of any number of parameters. This dynamic process forms the basis for clearly defining phenomena as flame or no flame. This is ultimately decisive in the detection process for deciding whether to actuate an alarm. 3
The patented handshake - Fuzzy Logic and Wavelet Technology. The mathematically correct reproduction of the standard flame and its parameters is achieved with two procedures. When combined they produce unique results. Detector Flame Wavelets Wavelets Sensors give mathematically-describable signals. The comparison of complex forms of signal development calls for vast computer capacity. To avoid this, Wavelet Technology is used to break down the signal curve into a typical sequence of images which can be described concisely and distinctly. Comparing different forms of signal development involves comparing individual sequences. This comparison of patterns of typical signals is efficient and fast. Signal analysis Decision process Decision Alarm Signal Algorithms No alarm Fuzzy Logic Patented combination of Fuzzy Logic and Wavelets: In the flame detector, the signals measured are compared with the stored similarity factors of genuine flame signals. Fuzzy Logic Digital processes operate with distinct YES / NO decisions. Something is either red or it is yellow. However, in nature gradual differences are the norm. Distinct differences are the exception. A little red, not so much yellow, or half red are definable as degrees of affiliation. Related to flames, this means: 30% flame and 70% no flame. The combination of Fuzzy Logic and Wavelet Technology thus enables highly precise and yet rapid sample recognition. This is patented and only available from Siemens. The advantages are evident: Highly reliable detection and immunity to deceptive phenomena Extremely precise and rapid alarm decisions Optimum detector price-performance ratio By the way: Wavelet Technology is also used to stabilize helicopter flight, to analyse the curves of seismic blasting in oil exploration, to verify astronomical models, or even to precisely filter out one fingerprint in a million. 4
More than three magic eyes. The structural design of the detector is as robust as it is ingenious. The sensors supply precise data to the evaluation logic described here. Two sensors look the flame in the eye Two pyrosensors are responsible for the spectral analysis of the flame. In the process, the infrared radiant energy emitted is measured on two different wavelengths and its flicker frequency is examined. The Siemens flame detector is superior thanks to its wide monitoring angle and its extensive monitoring area. A third sensor observes the sunlight Sunlight is one of the most frequent interference factors for flame detectors. In order to identify it and eliminate it as a source of deceptive alarms, a sunlight sensor is provided. Other outstanding features include: Robust mechanical design for use even under the most difficult environmental conditions. Temperature ranges from -35 C to +70 C. Various detection algorithms - adjustable on the detector itself - for different application environments. Detectors in intrinsically safe enclosures Siemens flame detectors are also available as digital comparators and are thus also suitable for connection to other manufacturers` control units. 5
All clear for Siemens Flame Detectors! Siemens flame detectors are ideally suitable for monitoring zones in which outbreaks of open fire are expected. Its wide monitoring radius and the detection even of smaller flames at long distances also make it the ideal detector for large, open-plan structures. Its high immunity to solar radiation and its solid design mean it can also be used without any difficulty in the open air: aircraft hangars underground chambers storage facilities containing readily flammable materials and tank farms malls filling plants and transhipment terminals shopping centres libraries garages ferries loading ramps turbine installations and power stations For detailed technical data, please refer to the product data sheet available separately. To manufacturers who wish to improve the performance, reliability and - at least - the profitability of their own product range we offer innovative customized OEM versions of our products to meet their individual business and manufacturing needs. 6
Siemens Flame Detectors - Technical Overview. DF1191 DF1192 DF1101 Ex with one sensor for indoor applications with three sensors for indoor and outdoor applications with three sensors for indoor and outdoor applications compatible with all Siemens low voltage control units with SynoLOOP, AnalogPlus, collective and conventional signal evaluation compatible with all Siemens low voltage control units with SynoLOOP, AnalogPlus, collective and conventional signal evaluation compatible with all Siemens low voltage control units with collective signal evaluation, together with detection line coupler and shunt Zener diode barrier Eex ib IIC T4 Typical application examples. simple storage rooms in addition to smoke detectors usable without any interference sources like sunlight, halogen light, hot body radiation etc. large industrial stores Aircraft hangars Arc welding industry Power plants Transformer stations Printing press rooms Motor test beds Atria, Malls Wood stores Underground tunnels Ferries and cargo boats Ships engine rooms Chemicals production plants Chemicals stores Oil refineries Petrol storrage and pump stations Battery rooms Accessories. Rain hood protects the detector in outside applications Mounting bracket is used to fix the DF at the correct angle Ball and socket joint is used to line up the DF with the object to be monitored Test lamp is used for testing the operation of the DF on a range for alarm activation up to 10m Test lamp for explosion hazard areas is used to carry out a performance check on intrinsically safe DF in explosion-hazard areas in zones 1 and 2 7
Siemens Building Technologies Ltd. Fire & Security Products Alte Landstrasse 411 8708 Männedorf Switzerland Tel. +41 1 922 61 55 Fax +41 1 922 64 80 www.sbt.siemens.com/fsp Divisional Units in Australia, Austria, Belgium, Czech Republic, France, Germany, Italy, Malaysia, Netherlands, Norway, Poland, Singapore, Spain, Sweden, Switzerland and United Kingdom. Distribution Partners in more than 40 countries. Fire & Security Products Subject to change without notice Order no. Ae30057 Siemens Building Technologies Limited The information in this document contains general description of the technical options available, which do not always have to be present in the individual cases. The required features should therefore be specified in each individual case at the time of closing the contract.