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Technical Manual
Issue 2.4
afp-813
Quality system cert. no. 404
Assessed to ISO 9001

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Summary of Contents for STRATOS HSSD

  • Page 1 Technical Manual Issue 2.4 afp-813 Quality system cert. no. 404 Assessed to ISO 9001...
  • Page 2: Table Of Contents

    Dust Bargraph Scale Power Supplies Using an external power supply Chart recorder analogue output Examination of referencing systems Stratos detector referencing Local and remote referencing Terminal board jumper link connections Apollo Series 90 Interface Autronica BNX-3 Thorn AM521 Remote control software...
  • Page 3: Introduction

    Stratos-HSSD system. ¥ Help Lines AirSense Technology has taken every care to ensure that Stratos is as simple to install as possible, but in case of difficulty please contact our Help Line to ensure trouble free United Kingdom 01462 440666 installation.
  • Page 4: Heat Detectors

    T E C H N I C A L M A N U A L Background Many principles have been used to detect fire and are still in use, although some are only used in special applications. The following comments describe some of the more commonly used principles: Heat Detectors All fires give off heat, and sensing the temperature of the air at a given point in a given...
  • Page 5: General Optical Detectors

    T E C H N I C A L M A N U A L minimised, the combination of them, and the very small nature of the ionisation current (10 - 50 picoamps), limit the sensitivity and usefulness of ionisation detectors. It should also be noted that the use of radioactive elements is generally frowned upon by today’s society because of the difficulty in safely disposing of them.
  • Page 6: Light Scattering Detectors

    T E C H N I C A L M A N U A L Another type of optical detector is immediately suggested by the beam detector, when Light Scattering Detectors one considers what happens to the light in the beam that is not returned to the sensor. Very little of this light will be ‘absorbed’...
  • Page 7: Point Detectors

    T E C H N I C A L M A N U A L response time to fire may be rapid enough to detect flame within a few milliseconds, most fire situations will progress through a relatively long smouldering period, and generally light sensing detectors are either not sensitive to this stage or are inefficient at detecting it.
  • Page 8 T E C H N I C A L M A N U A L Any detector on the pair of wires which signals an alarm is signalled back to the control panel. This type of control panel is unable to say which of the many detectors had operated, so the signalling is only ‘zonal’.
  • Page 9: High Sensitivity Aspirating Systems (A.k.a. Air Sampling Systems)

    T E C H N I C A L M A N U A L are protecting; to give a rapid and sensitive alarm. The price paid for this degree of certainty is the time delay required for both detectors to trigger an alarm and the effective sensitivity are reduced to that of the least suitable detector of the pair.
  • Page 10 T E C H N I C A L M A N U A L placed, for example in an air extraction system or within smoke strata which may be anticipated. A high sensitivity aspirating detector can cover the same volume as many point detectors, but with added advantages.
  • Page 11: Specific Types Of Aspirating Systems

    T E C H N I C A L M A N U A L Thus the air sampling system can overcome most of the disadvantages of other detection methods, but tend to be economically designed to the limit of the market. (i.e.
  • Page 12: Particle Counters

    T E C H N I C A L M A N U A L Particle counters Particle counting works on the principle of counting the number of particles in a given volume of air sampled. In order to do this, the rate of air-flow through the chamber must be maintained within limits, or the effect of increased counting due to increasing the air-flow must be allowed for.
  • Page 13: Light Sources

    T E C H N I C A L M A N U A L true signal given by smoke, and the noise signals with sufficient reliability to prevent an alarm being triggered by the electrical noise. The amount of light scattered by a given volume of particles is highly dependent upon the wavelength of the light, with the amount of scatter increasing rapidly with a decrease in wavelength.
  • Page 14 T E C H N I C A L M A N U A L provides a very difficult problem to overcome where a detector is intended to behave as an absolute measuring instrument. Due to the deterioration in light output, the signal will deteriorate to a commensurate degree, requiring the detector to be frequently re calibrated.
  • Page 15: Absolute V. Relative Scaling

    T E C H N I C A L M A N U A L Absolute v. relative scaling Absolute Scaling The output of the smoke detector in the conventional aspirating smoke detector system is assumed to be (essentially) zero for a clean air sample and a fixed known level for a given amount of smoke pollution.
  • Page 16: Relative Scaling

    T E C H N I C A L M A N U A L The peaks indicated on the chart recorder may correspond to levels that should have triggered an alarm. The two weeks required for setting it up are inconvenient and are hence frequently omitted or reduced, and the alarm trigger levels set at a ‘safe’...
  • Page 17: Stratos-Hssd

    T E C H N I C A L M A N U A L Stratos is a relatively scaled detector designed around a modern microprocessor of the ® Stratos-HSSD same family as that used in Personal Computers. The detector chamber is based on the light scattering principle with a high power semiconductor laser used as the light source.
  • Page 18 T E C H N I C A L M A N U A L period had been several hours and it will take several hours before the distribution shows the true normal spread. The alarm trigger level is set by the spread, in terms of the standard deviation.
  • Page 19: Dust

    One indication that occurs for a relatively scaled detector (Stratos) is that the spread and level of readings will gradually decrease. Stratos will automatically decrease the scale range to compensate Page 19 ISSUE 2.4...
  • Page 20: Bargraph Scale

    The essence of the problem is not so much the filtering out of dust, which is a straight forward design problem, but the life of the filter, and giving a reliable indication that it is becoming fully loaded. The Stratos detector tackles the problem of dust in four ways;...
  • Page 21: Power Supplies

    See the installers handbook for the terminal board connector details. Stratos can be run from an external power supply which may be between 11 and 25 Using an external power supply Volts.
  • Page 22: Chart Recorder Analogue Output

    Outside sources of smoke pollution may easily rise to levels above 10% obs/m., more than a hundred times the alarm level of a high sensitivity air sampling detector system such as Stratos. Where such situations are likely, Page 22 ISSUE 2.4...
  • Page 23 [10] - [10] = [0] regardless of pollution added within the area Stratos™ solves this problem by ensuring the detector is always able to go into alarm using it’s patented ClassiFire™ technology. However there is another problem which Page 23 ISSUE 2.4...
  • Page 24 T E C H N I C A L M A N U A L cannot be solved by the designer of the detector but must be solved by the system designer. This is the transient problem of the changes which occur when pollution starts to be detected at the inlet and when it ceases to be detected.
  • Page 25 T E C H N I C A L M A N U A L At the onset of pollution at the inlet the pollution at the outlet will not immediately rise to the same level. For a pollution level of X% arriving at the inlet, the pollution level at the outlet will rise with the inverse exponential of time towards X% and in theory never actually reach it.
  • Page 26 T E C H N I C A L M A N U A L The SOURCE is considered as the point where pollution from an external source enters the controllable system. In most cases this is the building in which the protected room is sited.
  • Page 27 T E C H N I C A L M A N U A L the detector is in a state of low sensitivity. This is one of the major errors the system designer is trying to avoid by using a reference system. The exact duration of this period and the extent of the low sensitivity will be assessed later from a mathematical analysis.
  • Page 28 T E C H N I C A L M A N U A L For the case when pollution is increasing in the Cs = pollution at the source. room:- Cr = pollution in the room. -t / T Cr = Cs 2 ( 1 - ˆ...
  • Page 29 T E C H N I C A L M A N U A L the alarm level and 0.1% to overcome the residual reference signal. The time taken for the pollution level at the outlet to rise is “t” in the equation: -t/T = Cs 2 ( 1 - ˆ...
  • Page 30 T E C H N I C A L M A N U A L source. In this case no reference system would be required to compensate for it. The main factor in the determination of time in alarm or time in low sensitivity is the time constant “T”.
  • Page 31 T E C H N I C A L M A N U A L Fig. 5. Complex situation with more than one room serviced by a single air Outlet Inlet conditioning unit. Room A Outlet Inlet Fresh Air Room B Make up Source Exhaust Outlet...
  • Page 32: Stratos Detector Referencing

    Stratos does contain a function to program in the filling time constant which is separately programmable for each detector in a system. The variations of smoke density and signals associated with this are shown in Fig.
  • Page 33 T E C H N I C A L M A N U A L room resulting in an inverse exponential change of pollution within the room, as previously explained. Providing that the external pollution level is not exorbitantly high, some trial and error adjustments around the setting of the “Reference back off time delay (mins)”...
  • Page 34: Local And Remote Referencing

    T E C H N I C A L M A N U A L Local and Stratos is provided with the facility to use a Reference signal to combat unwanted alarms remote caused by smoke from outside sources drawn into a protected areas.
  • Page 35: Terminal Board Jumper Link Connections

    T E C H N I C A L M A N U A L Using a Slave detector as a local reference does not reduce the number of slaves available on the slave loop. The remote reference cable is a screened 2-core cable. Patch links are used on the terminal board to configure the line connections for different Terminal board interface boards.
  • Page 36: Autronica Bnx-3

    T E C H N I C A L M A N U A L Autronica BNX-3 Single Master Master + 1 Slave Master + 2 Slaves Master + 3 Slaves Line connections Line in +ve Line 1 Line out +ve Line 2 Line in -ve Line 3...
  • Page 37: Thorn Am521

    T E C H N I C A L M A N U A L Thorn AM521 Single Master Master + 1 Slave Master + 2 Slaves Master + 3 Slaves Line connections Line in -ve Line 1 Line in +ve Line 2 Line out -ve Line 3...
  • Page 38: Remote Control Software

    This access code is the same code that is entered in functions 01 and 02 on the programmer on the back of the front panel. The Stratos remote software is fully menu driven for ease of use and consists of three major parts; setup menu, demonstration and log menu and diagnostic menu. These are covered more fully below.
  • Page 39 Front panel The front panel keys on a Stratos master can be individually enabled or disabled. Note that disabling a key on the front panel of the Stratos master has the same effect on the mimic, if connected. Power monitoring Battery check or mains check can be enabled or disabled.
  • Page 40: Demonstration And Log Menu

    F1-F4. Chart recorder log Stratos has the facility of storing a chart recording in it’s memory of up to a month (depending on the sampling rate). This menu item displays the chart recording in a graphical format.
  • Page 41: Diagnostic Menu

    This menu item shows the detector output and air flow rate as continuously varying percentages. Press any key to end the display. Controller diagnostics The control board is the board on the front panel of the Stratos. All circuits tested are followed by a pass/fail. Slave loop error rate Interference on the slave loop can cause corruption of the data passed between a master and it’s slaves.
  • Page 42: Chart Recorder Format

    T E C H N I C A L M A N U A L Status report Runs detector diagnostics and controller diagnostics; dumps the event log and histogram and prints the function settings. This function is designed to be used as a final commissioning check to take a complete status report.
  • Page 43: Histogram Format

    Minutes left of FastLearn otherwise zero if no FastLearn word Alarm factor word The shaded areas on the histogram packet have been changed for revision 3.2 of the Stratos software. Product id numbers The product id numbers stored in the histogram data packet are shown below. Number Product...
  • Page 44: Remote Monitor Format

    M A N U A L Extended remote monitor mode is not supported by the remote software but is Remote monitor format provided for other products that remotely access the Stratos range of detectors like SenseNET™. Information Size Product id of detector (see above)
  • Page 45: Remote Monitor Programming Api

    T E C H N I C A L M A N U A L When the detector is in remote monitor mode it is possible to send program commands Remote monitor programming API to set function values and isolate, reset or test the detector. API programming strings consist of one or more commands terminated with a carriage return (CR).
  • Page 46: Chart Recorder Sample Rates

    T E C H N I C A L M A N U A L The following strings allow programming of the functions. These commands are preceded by ‘>’ (0x3e). The command string should be terminated with a CR character (0x0d). Note that to prevent the command string being terminated by a 0x0d in the command being interpreted as end of string all binary parameter values have 0x7f (127 decimal) added to them.
  • Page 47: Pipecad™ For Windows

    PipeCAD takes both laminar and turbulent air flow types into account, and offers unequalled accuracy in sampling pipe design. Due to the extremely high air flow characteristics of the Stratos Aspirator, PipeCAD is incompatible with other aspirating smoke detection system types.
  • Page 48: Airsense Technology Ltd

    Tel. +822 404 0417 • Fax. +822 404 1206 e-mail: airsense@nownuri.net In line with continuous product improvement AirSense Technology Ltd. reserves the right to modify or update specifications without notice. Stratos, HSSD, AirSense, ClassiFire and FastLearn are registered trade marks of AirSense Technology Ltd.

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