User manual SCUBAPRO-UWATEC ALADIN AIR Z O2

THE SYSTEM OPERATING MANUAL ® Active Light English ® SWISS MADE BY UWATEC AG AIR Z O2 English Operating scheme for surface functions B and E B and + B and ­ 1 5 Sleep Surface Sleep 2 4 Input stage O2 % MIX (or 3min) min) Ready or Surface automatically 3 5sec Input stage (or 3min) (or 3m LOGBOOK (or 3 in) O2 % MIX Battery capacity dive time LOGBOOK depth DO NOT FLY LOGBOOK CNS O2 LIMIT S L O W % NO STOP max. depth tank data deco info tank data bar % bar 2 Uwatec® Aladin® Air Z O2 Important remarks concerning signal words and symbols This operating manual makes use of the following icons to indicate especially important comments: Remarks: Informations and tips which are important for optimal use of the functions of your Aladin® Air Z O2. Informations and tips which are important for optimal use of the functions of your Aladin® Air Z O2. English Attention: Danger! Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury. The following symbols are used in the operating manual: Flashing display Acoustic alarm signal -+E B Only valid if an Oxy2 is used Only valid if a pressure transmitter is used January 2000, Copyright by Uwatec Switzerland Uwatec® Aladin® Air Z O2 Operating instruction for manual input Example: bridging contacts B and E 3 Safety considerations You must carefully read and understand this entire manual before using your Aladin® Air Z O2. Diving has many inherent risks. Even if you follow the instructions of this manual in a careful manner, it is still possible that you may be seriously injured or die from decompression sickness, oxygen toxicity or some other inherent risk of scuba Nitrox or compressed air. Unless you are fully aware of these risks and are willing to personally accept and assume responsibility for those risks, do not use the Aladin® Air Z O2! The Aladin® Air Z O2 is a decompression tool to assist a trained and certified diver in making decisions (there is no dive planner available in the Air Z O2). As with any tool, the Aladin® Air Z O2 may be misused if the following safety and operational precautions are not strictly followed. If they are followed, careful use of the Aladin® Air Z O2 can increase your diving enjoyment and reduce your risk of decompression sickness. If they are not, you will be placing yourself at serious risk for decompression sickness. While the Aladin® Air Z O2 is a technically advanced tool based on mathematical models of decompression sickness and oxygen toxicity, neither it nor any other diving computer (or table) can actually monitor the physiological changes that occur in your body as you dive. In addition, each diver will vary in his or her susceptibility to decompression sickness. In addition, each diver will vary in his or her susceptibility to decompression sickness and each individual diver`s own susceptibility may vary from day to day. Combined with the fact that decompression modelling is an inexact science, and must be based to some extend on certain unproven assumptions, it is emphasis on you, the individual diver, to dive responsibly and to carefully follow all standard safe diving practices as well as the recommendations contained in this manual. Guidelines for the use of Aladin® Air Z O2: The following guidelines for using Aladin® Air Z O2 are derived from the latest medical research for diving with diving computers. Following these guidelines will greatly increase your safety while diving, but cannot guarantee that decompression sickness will not occur. ­ The Aladin® Air Z O2 is designed for dives with nitrox (max.99 %O2)and compressed air (21%O2) only. Do not use the Aladin® Air Z O2 for dives made with other mixed gases. ­ It is essential to check the set mixture or O2 fraction before each dive and to compare it to the gas mixture to be used, even if you are using an Oxy2. Always remember: Setting a wrong mixture causes eit- 4 Uwatec® Aladin® Air Z O2 Safety considerations her insufficient decompression calculations or a too low calculation of the oxygen-toxicity! ­ Always check the diving limits considering the oxygen content and standard sports diving procedures (decompression sickness, oxygen toxicity). ­ Do not dive deeper than 40 metres. ­ The danger of nitrogen narcosis has to be taken into consideration for all dives regardless of the gas mixture. The Aladin® Air Z O2 gives no warning about this. ­ On all dives with the Aladin® Air Z O2, make a safety stop for at least one to three minutes within the 3 to 5 metre zone. ­ Always make the deepest dive of the day first when repetitive dives are planned, and for each dive make sure that the deepest portion of that dive is done at the beginning of the dive. ­ If your diving cylinder is equipped with a reserve or "J"-type valve, make certain that the reserve function is in an open (down) position. Failure to keep the reserve open will result in the improper calculation of the dive data which depends on tank pressure. ­ All divers using dive computers to plan dives and indicate or determine decompression status must use their own computer which they take with them on all dives. ­ If the Aladin® Air Z O2 fails at any time during the dive, the dive must be terminated, and appropriate surfacing procedures should be initiated immediately. ­ On any given dive, all divers in a buddy group must follow the most conservative dive computer for that particular dive. ­ Repetitive dives after exchanging the dive computer: Wait at least 24 hour before you start with the repetitive dive. ­ You MUST be familiar with all signs and symptoms of decompression sickness before using the Aladin® Air Z O2! Seek IMMEDIATE treatment for decompression sickness should any of these signs or symptoms occur after a dive! There is a direct correlation between the effectiveness of treatment and the delay between the onset of symptoms and the treatment for decompression sickness. ­ Always observe the optical and acoustic alarm signals of the Aladin® Air Z O2. Avoid situations of increased risk which are marked with a warning sign in this operating manual. ­ If the ascent arrow appears in the lower display window, start ascending. ­ If the flashing ascent arrow appears in the lower display window, start to ascend immediately. ­ See also page 10, 74-76, 100. Uwatec® Aladin® Air Z O2 5 English Aladin® Air Z O2 ­ The Diving System Oxy2 (Option) + E MemoMouse and logbook software DataTrak (Option) Pressure Transmitter (Option) B Dive Computer Aladin® Air Z O2 Screen Guard (Optional: several colours) 6 Uwatec® Aladin® Air Z O2 List of chapters I 1 2 3 4 Aladin® Air Z O2 ­ Introduction _______9 Aladin® Air Z O2 ­ Introduction __________10 Aladin® Air Z O2 ­ More Safety in Diving __10 Aladin® Air Z O2 ­ Your Personal Companion __________________________13 The Calculation Model ZH-L8 ADT 4.1 Description _______________________14 4.2 Advantages _______________________16 Safety in Diving _______________________16 Aladin® Air Z O2 ­ The System ________17 Description 1.1 Structure _________________________18 1.2 Reliability of transmission ___________19 Pressure transmitter and Oxy2 2.1 Pressure transmitter operating modes and functions _______________20 2.2 Oyx2 operating modes and functions _21 2.3 Data transmission and reception _____22 Dive Computer 3.1 Operation ________________________23 Acticve backlight __________________24 3.2 Operating modes __________________29 Setting Up (Oxy2, press. transmitter and Aladin® Air Z O2) 4.1 Fitting the Oxy2 to a rebreather______34 4.2 Fitting of pressure transmitter _______35 4.3 Remarks about pairing _____________37 4.4 How to check that the computer is paired correctly __________________38 4.5 Pairing of Oxy2 and dive computer ___38 4.6 Pairing of press. transmitter and dive comp. ___________________________40 III Diving with Aladin® Air Z O2 _________41 1 Terminology/Symbols 1.1 Deco data during no-stop phase _____42 1.2 Display during decompression phase__43 1.3 Indications on the lower display______43 1.4 Nitrox information _________________44 2 Attention Messages and Alarms 2.1 Attention Messages ________________46 2.2 Alarms ___________________________49 2.3 Alarm low battery _________________51 3 Preparation for a Dive 3.1 Preparation for a Dive with Oxy2_____51 3.2 Preparation for a Dive with press. transm. __________________________53 3.3 Setting the gas mixture _____________54 4 Functions during the Dive 4.1 Dive time_________________________55 4.2 Current depth_____________________56 4.3 Maximum depth___________________56 4.4 Ascent rate _______________________57 4.5 Partial pressure of oxygen (ppO2)_____59 4.6 Oxygen toxicity (CNS O2%)__________59 4.7 Oxygen fraction of the inspired gas mixture _______________________61 4.8 Decompression information _________61 4.9 Tank pressure _________________63 4.10 Increased workload warning________64 4.11 Interruption of transmission ________65 5 II 1 2 3 4 Uwatec® Aladin® Air Z O2 7 English List of chapters 5 4.12 Remaining Bottom Time RBT ___65 Functions at the Surface 5.1 End of a dive _____________________67 5.2 Desaturation time _________________68 5.3 No fly time _______________________68 5.4 Warning of bubbles ________________69 Diving in Mountain Lakes_______________70 VII Trouble Shooting ____________________91 1 Trouble Shooting ______________________92 VIII 1 2 3 4 Appendix ___________________________95 Maintenance _________________________96 Technical Information __________________97 Conversion of tank pressure ____________98 Warranty 3.1 Recognition of warranty ____________99 3.2 Scope of the warranty______________99 3.3 Warranty period and claim __________99 Safety considerations _________________100 Serial No. / Dealer address _____________102 6 IV Diving at Reduced Risk with Aladin® Air Z O2 _____________________73 1 Diving at reduced risk with Aladin® Air Z O2 1.1 Diving at reduced risk ______________74 1.2 Diving at reduced risk for the first dive 74 1.3 Minimizing risk on repetitive dives____75 1.4 Response in increased risk situations __76 V 1 2 3 4 5 Logbook ____________________________81 Survey _______________________________82 Selection and Activation________________83 Selection of Dive ______________________84 Leaving the Logbook-Mode ____________85 Output on PC ________________________86 5 6 IX Index ______________________________103 VI Communication Software for Windows® _______________________87 1 MemoMouse, DataTrak and DataTalk 1.1 Personal programming of the dive computer (DataTalk) ___________88 1.2 Analysis and storage of real dives (DataTrak) ___________________89 1.3 Updates (DataTrak, DataTalk) ________89 8 Uwatec® Aladin® Air Z O2 I Introduction 1 2 3 4 Aladin® Air Z O2 ­ Introduction Aladin® Air Z O2 ­ More Safety in Diving Aladin® Air Z O2 ­ Your Personal Companion The Calculation Model ZH-L8 ADT I _________________________________________10 _________________________________________10 _________________________________________13 4.1 Description ____________________________14 4.2 Advantages____________________________16 _________________________________________16 English 5 Safety in Diving I Uwatec® Aladin® Air Z O2 9 1 Aladin® Air Z O2 ­ Introduction When you dive with an SCR with Oxy2 and Aladin® Air Z O2 you will know your exact decompression, CNS clock status, Oxygen fractions and ppO2 on line and in real time. With Aladin® Air Z O2 paired to a pressure transmitter or Oxy2 you dive more safely than ever before, though you can make more of your diving time thanks to the exact calculation of the gas-supply. In addition, Aladin® Air Z O2 offers an unmatched comfort in carrying and operation. Aladin® Air Z O2 gives you increased safety due to it`s calculation model. All the information necessary for safe diving are combined in one instrument. With the Aladin® Air Z O2 you are ­ due to it`s multi-function ­ ready for the future. The Aladin® Air Z O2 can increase both your diving pleasure and safety by reducing your risk of decompression sickness provided you carefully follow the instructions and guidelines given you in this manual. Unlike previous diving computers, which only base their decompression information on depth and time data, the Aladin® Air Z O2 also considers temperature and diver workload, which are known to be additional risk factors for decompression sickness. By considering these risk factors as well as monitoring your exact supply, the Aladin® Air Z O2 allows you to plan and execute dives with a greater degree of safety than with previous models of decompression computers. The Aladin® Air Z O2 and the Oxy2 are not to be used with closed circuit rebreathers. Please read this operating manual carefully and to the last page. If you are using an Oxy2, you must also carefully read the Oxy2 manual. 2 Aladin® Air Z O2 ­ More Safety in Diving Nitrox is a gas mixture consisting of nitrogen and oxygen. The kind of air used for diving with compressed air is the same as the normal air of the earth`s atmosphere (78% nitrogen, 21% oxygen and 1% inert gases). Therefore, normal air is also Nitrox! When talking of Nitrox as the breathing gas for diving, it describes a mixture with a higher percentage of oxygen. A higher percentage of oxygen (and automatically the reduction of nitrogen) has the advantage of lengthening the no-stop phase (or reducing the decompression phase), since less nitrogen is dissolved in the diver`s body during the dive. 10 I Uwatec® Aladin® Air Z O2 2 Aladin® Air Z O2 ­ More Safety in Diving I The higher share of oxygen in the Nitrox-mixture also causes additional physiological problems by the toxic effects at a higher partial pressure of oxygen (ppO2). When breathing oxygen at a higher partial pressure, two kinds of oxygen toxicity can occur: · CNS damages: Symptoms of poisoning occuring at short notice in the central nervous system (CNS). Such symptoms are: irritations of the respiratory organs, sickness, headache, pulmonary oedema, cramps, unconsciousness. The symptoms occur at a ppO2 of more than 1 bar and depend on the term of exposure and on the partial pressure of oxygen. · Damages of the lungs: Symptoms of pulmonary poisoning occuring in the long run. The symptoms occur at a ppO2 from 0.5 bar and higher and with terms of exposure in the range of hours/days. Aladin® Air Z O2 considers the short term toxic effect of oxygen (CNS damages) by means of the so called ,,oxygen-clock". It is based on a list which shows the units of toxicity for oxygen per unit of time and is dependent on the ppO2. The indication of toxicity is shown as ,,CNS O2%" (= relative toxicity of oxygen for the central nervous system). CNS O2 LIMIT = 0% corresponds to the normal state before the first dive, and CNS O2 LIMIT =100% corresponds to the critical upper limit. The list, initially published by the US Navy, is nowadays known by the name NOAA-list. We modified this list for the use with Aladin® Air Z O2 in cooperation with Dr. Bill Hamilton, Hamilton Research Ltd. (Tarrytown, NY), a well-known specialist. The long term kind of oxygen poisoning has practically no relevance for diving with independent diving equipment and is therefore not considered in the design of Aladin® Air Z O2. If nitrox is used for diving profound additional training is needed because of the physiological peculiarities of oxygen and the changing decompression due to the reduced percentage of nitrogen. Additional technical problems with the use and the maintenance of parts of the equipment are additional potential dangers when diving with nitrox or rebreathers. Therefore, we recommend strict adherence to the following guidelines and warnings. I Uwatec® Aladin® Air Z O2 11 English 2 Aladin® Air Z O2 ­ More Safety in Diving 1. Only dive with nitrox or SCR if you have been trained thoroughly by a recognised agency. 2. Only use the pressure transmitter with open breathing systems. Aladin® Air Z O2 must be set for a determined gas mixture. In partially-open and in closed circulationsystems, the gas mixture in the breathing loop can vary considerably from the mixture in the tank(s). 3. For dives with an SCR always use an Oxy2. 4. Aladin® Air Z O2 when used with Oxy2 does not show the tank pressure nor related warnings. Check the pressure gauge frequently. 5. Only use Aladin® Air Z O2 for diving with an independent breathing apparatus. Aladin® Air Z O2 is not designed for long-term exposures with Nitrox. 6. If a pressure transmitter is used the Aladin® Air Z O2 always calculates based on the gas mixture set by the user. Before each dive it is essential to check that this mixture setting is correct for the actual gas mixture to be used. Maximum deviation from the mixture calculation must not exceed 1% O2. A wrong gas mixture can be lethal!. 7. Aladin® Air Z O2 has a ppO2-warning, the default-limits of which are set at 1.5 bar ppO2 max. This limit can be adjusted via MemoMouse/Data Talk in the range of 1.2 to 1.95 bar. An alternation of the ppO2 max to higher than 1.6 bar is risky and is not recommended. 8. Frequently check the ,,oxygen-clock" (CNS O2%), especially when the ppO2 is greater than 1.5 bar. Finish the dive if the CNS O2% exceeds 75%. 9. Make sure you have a sufficiently long surface interval, just as when diving with compressed air. Oxygen also needs sufficient time to leave the body. Go on the next dive only when the CNS O2% has dropped below 40%. 10.Aladin® Air Z O2 is a personal instrument like any other diving computer. This still applies when diving with compressed air (21% oxygen) between two nitrox-dives. Aladin® Air Z O2 can be adjusted to compressed air and then also includes the calculation of the CNS O2% in the same way as with any other nitrox-dive. 11.Always remember: setting a wrong mixture causes either insufficient decompression calculations or a too low calculation of the oxygen-toxicity! 12 I Uwatec® Aladin® Air Z O2 3 Aladin® Air Z O2 ­ Your Personal Companion I Aladin® Air Z O2 considers your individual gas mixture, depth and time profile, as well as workload and water temperature. Relying on the latest results of medical and physiological research for its decompression modelling, the Aladin® Air Z O2 differs from other diving computers in a number of significant ways: · Diving with SCR and Oxy2 enables the calculation of oxygen toxicity and decompression to be on the basis of the actual composition of the inhaled gas. · The Aladin® Air Z O2 indicates on the lower display the actual oxygen percentage, the ppO2 and if needed O2 attention messages and alarms. · The workload is calculated from the difference between the automatically registered oxygen fraction of the premixed gas and the actual oxygen percentage of the inspired gas mixture. The sensitivity of the workload detection can be adjusted with DataTalk. Also the diver selected maximum O2 consumption supported by the SCR has to be programmed in with DataTalk. · The ZH-L8 ADT decompression calculation model considers eight body tissues as well as the diver`s workload and ambient temperature. This allows for a more precise calculation of a modelled risk for decompression sickness which can lead to greater diving safety. · The gas data ­ measured by an Oxy2 or a pressure transmitter ­ are transmitted by wireless to the Aladin® Air Z O2. Faulty transmission of data between the transmitter and Aladin® Air Z O2 is prevented by a number of precautions. · If a pressure transmitter is used, the tank pressure can be easily checked at any time. By monitoring the pattern of the changes in gas pressure, the Aladin® Air Z O2 calculates the diver`s workload and provides a prediction of the remaining time allowed at the current depth based upon tank pressure and air consumption. Thus the remaining bottom time (RBT) displayed on the Aladin® Air Z O2 considers depth, tank pressure, as well as gas consumption to give the diver a more accurate calculation of when the ascent must be begun according to the decompression program. If a tank with a reserve or "J"-Type valve is used, the reserve must be in the open (down) position in order to receive a correct remaining bottom time (RBT) calculation. · The Aladin® Air Z O2 uses both optical and acoustic alarms. The acoustic alarm uses varied sound signals to assist in identifying the reason for the alarm. I Uwatec® Aladin® Air Z O2 13 English 3 Aladin® Air Z O2 ­ Your Personal Companion / 4 The Calculation Model ZH-L8 ADT You must strictly observe all optical and acoustic alarms and take appropriate action based upon those alarms to avoid serious injury or death from decompression sickness! · By using the Aladin® Air Z O2`s logbook, a diver may directly call up information from the last 19 dives. The last 37 dives and 175 minutes of dive profile in intervals of 20 seconds can be read out into a MemoMouse, which can be later interfaced with a personal computer (windows). The MemoMouse can store up to 58 hours of diving data. · The Aladin® Air Z O2 is designed to be mounted on the diver`s left or right wrist, which offers the maximum freedom of movement as well as easy operation and use. 4 The Calculation Model ZH-L8 ADT 4.1 Description The Aladin® Air Z O2 uses the decompression calculation model known as the ZH-L8 ADT. This model uses eight compartments or "tissue" groups with nominal half time periods from 5 to 640 minutes. This model differs considerably from other models by its consideration of the following additional physiological processes: 1.Blood perfusion to the body`s organs is not constant. Skin and muscle tissues are in particular subject to changes in blood perfusion, depending on temperature and workload. Changes in blood perfusion to these organs change their nitrogen saturation tolerance. The model used by the Aladin® Air Z O2 takes these effects into account and thus the "skin" and "muscle" compartments in the Aladin® Air Z O2 show variable half-time periods and saturation tolerances. Decompression information is calculated according to the diver`s individual workload and decrease in skin temperature. The decrease in skin temperature is based upon the water temperature and the dive time. By considering these changes in saturation, the time that must be spent at the surface prior to flying may be considerably increased, depending upon the depth, time, and temperature of a dive, as well as the diver`s workload during that dive. 2.The decompression model used by the Aladin® Air Z O2 considers nitrogen in both its dissolved as well as its gaseous phase (microbubbles). Formation of microbubbles is considered to be a strong indicator of a high risk of decompression sickness. The Aladin® Air Z O2 model calculates the formation of micro- 14 I Uwatec® Aladin® Air Z O2 4 The Calculation Model ZH-L8 ADT I bubbles depending on various assumed influences in arterial and venous blood. In normal, slow ascents, microbubbles form mainly in venous blood. During fast ascents, microbubbles may also form in arterial blood and in the body`s tissues as well. If a particular dive profile may result in the creation of microbubbles according to the Aladin® Air Z O2`s model, decreased bottom time and/or increased decompression times as well as increased "no fly" time will be indicated. · Microbubbles can form if the diver makes too fast an ascent, ignores required decompression stops, or makes repeated ascents during a dive (yo-yo diving). These microbubbles can form in arterial blood as well as in the body`s tissues. If these microbubbles partially impair circulation, the rate of gas diffusion and saturation tolerance for those tissues immediately surrounding this area of impaired circulation are changed. If required, both decompression time and RBT will be adjusted in such a way that already existing microbubbles will stop growing. Increased decompression time will also assist those local areas of impaired circulation to desaturate with less risk of decompression sickness. · The calculation of microbubbles results in altered ascent instructions. If microbubbles are assumed to be present based on the data used by the Aladin® Air Z O2, the ascent rate to the surface is reduced to 7 metres/minute. This will help prevent the formation of microbubbles in the arterial circulation and minimizes formation of microbubbles in the venous circulation after the dive. 4.2 Advantages On the first dives following responsible diving procedures, a diver using the Aladin® Air Z O2 should never require decompression stops, although a one to three minute safety stop between 3 and 5 metres is recommended for every dive. If, however, unplanned circumstances arise during the dive which increase the risk of decompression sickness, the Aladin® Air Z O2 can, if closely followed, reduce the risk by reducing remaining bottom time and/or increasing decompression time. Some of the more common risk situations are as follows: · · · · · Repetitive dives, especially those deeper than 20 metres and those with short surface intervals. Repetitive diving over the course of several successive days. Diving in cold water. Diving with increased workloads. Yo-yo diving (repeated descents and ascents to the surface during a given dive). English I Uwatec® Aladin® Air Z O2 15 4 The Calculation Model ZH-L8 ADT / 5 Safety in Diving · Flying within 24 hours after diving. · Excessive ascent rate. If a diver experiences any of these risk factors while diving, the Aladin® Air Z O2 will decrease remaining bottom time without requiring decompression, or will add required decompression time in order to help minimize the risk of decompression sickness. If signs or symptoms of decompression sickness occur after diving with Aladin® Air Z O2, seek IMMEDIATE treatment at the nearest recompression facility. 5 Safety in Diving Together with an Oxy2 or pressure transmitter the Aladin is an extremely versatile tool which can increase your diving comfort and safety. As with any diving tool, however, ultimate responsibility for diving safety remains with the individual diver. The same responsible diving practices taught by all diving certification agencies are still absolutely necessary in order to safely dive with the Aladin® Air Z O2. Certain mistakes which may be made by a diver, such as ascending at an excessive rate, going too deep, or staying too long at depth, may be overcome if the diver carefully follows the Aladin® Air Z O2`s corrected ascent instructions. Of course, the Aladin® Air Z O2 can do nothing to prevent the occurrence of lung overexpansion injuries or nitrogen narcosis, whose avoidance lies solely with the individual diver. The Aladin® Air Z O2 is a highly sophisticated technical instrument which, if used and maintained properly, will have high reliability. Despite this no dive should be made with an Aladin® Air Z O2 without a thorough understanding of decompression theory and dive table use, and every diver must have a set of decompression tables with him on every dive. Do not use the Aladin® Air Z O2 without a set of accepted nitrox diving tables with you as a back up decompression tool on every dive. Should decompression sickness occur, whether the Aladin® Air Z O2 was used correctly or not, a detailed history of the previous dives may be used to allow a better diagnosis and the most effective treatment for the diver. 16 I Uwatec® Aladin® Air Z O2 II Aladin® Air Z O2 ­ The System 1 Description 1.1 1.2 2.1 2.2 2.3 3 Dive Computer 3.1 3.2 4 Setting Up (Oxy2, press. transmitter, Air Z O2) 4.1 4.2 4.3 4.4 4.5 4.6 II Structure _________________________________18 Reliability of transmission____________________19 Pressure transmitter operating modes and functions _________________________________20 Oyx2 operating modes and functions _________21 Data transmission and reception _____________22 Operation_________________________________23 Acticve backlight___________________________24 Operating modes __________________________29 2 Pressure transmitter and Oxy2 Fitting the Oxy2 to a rebreather ______________34 Fitting of pressure transmitter ________________35 Remarks about pairing ______________________37 How to check that the computer is paired correctly __________________________________38 Pairing of Oxy2 and dive computer ___________38 Pairing of press. transmitter and dive comp.____40 II Uwatec® Aladin® Air Z O2 17 English 1 Description 1.1 Structure The Aladin® Air Z O2 system consists of four units: 1 1 3 The Oxy2 is fitted "in line" to the inhalation hose of the semi closed rebreather (SCR) and measures the actual oxygen fraction of the inspired gas mixture. This information is transmitted to a paired wireless Aladin® Air Z O2. This is the basis for the calculation of both oxygen toxicity and decompression, based on the real values of the inhalation gas. With open circuit breathing systems a pressure transmitter is used, which is installed at the high pressure outlet of the first stage regulator. It measures tank pressure and transmits the results to the dive computer, where they are further analysed for the calculation of gas mixture consumption and dive data. 2 3 3 The dive computer displays only important data. The upper display shows general dive data and decompression data. The lower display shows data from either an Oxy2 or pressure transmitter. 4 2 18 II Uwatec® Aladin® Air Z O2 1 Description depth DO NOT FLY LOGBOOK II dive time CNS O2 LIMIT S L O W % 4 The dive computer has a data memory which stores the dive data. The data can be downloaded out into a MemoMouse from where they can be transmitted to a Windows® personal computer with the logbook program DataTrak. MemoMouse and DataTrak are available as an option. English tank data NO STOP max. depth tank data deco info bar % bar It is possible to use Aladin® Air Z O2 as a conventional dive computer without pressure transmitter or Oxy2. In this case calculations depending on gas mixture data are not available and the lower part of the display will not show gas mixture data. 1.2 Reliability of transmission Data transmission from pressure transmitter or Oxy2 to receiver is supported by various levels of redundancy in order to warrant undisturbed and reliable reception: 1.Each Oxy2 or pressure transmitter works with an allocated address. This address is communicated to the dive computer on pairing. There are more than 60,000 addresses. The pairing of transmitter and receiver is also carried out by a process with various safety levels in order to prevent faulty pairing. 2.Data are transmitted with an average interval of 5 seconds. The exact point in time of the transmission is variable. This prevents two transmitters from disturbing each other for longer periods. II Uwatec® Aladin® Air Z O2 19 1 Description 3.Together with the data additional information is transmitted. This additional information allows the Aladin® Air Z O2 to reconstruct faulty data and recognize useless data. By means of these redundant measures, faulty transmission is almost impossible. These transmitted measurements are subjected to an additional plausibility check. Only such data are used which are sensible in the current situation. 2 Pressure transmitter and Oxy2 2.1 Pressure transmitter operating modes and functions Off-mode: When the tank valve is turned off and the regulator purged the pressure transmitter is in the off-mode. In that case, gas mixture pressure is measured every 5 seconds. When pressure increases (on opening the valve), the pressure transmitter leaves the off-mode automatically. When the tank-valve is closed and the regulator purged (pressure sinks below 8 bar), the transmitter falls back into off-mode. Pair-mode: After switching on (opening the tank valve), the pressure transmitter sends its address to the dive computer for a short time. During this time the dive computer can be paired to the pressure transmitter. As long as tank-pressure is decreasing (during normal breathing) the pressure is transmitted to the dive computer on average every 5 seconds. II Uwatec® Aladin® Air Z O2 Transmission-mode: 20