Shearwater NERD 2 Manual
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Shearwater NERD 2 Manual

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Operating Instructions
MANUAL
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  • Page 1 Operating Instructions MANUAL Revision A...

  • Page 2: Table Of Contents

    Shearwater NERD 2 — User Manual CONTENTS INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 MODELS COVERED BY THIS MANUAL .
  • Page 3 CHARGING THE NERD 2 . . . . . . . . . . . . . . . . . .
  • Page 4 Shearwater NERD 2 — User Manual DANGER This computer is capable of calculating deco stop requirements . These calculations are at best a guess of the real physiological decompression requirements . Dives requiring staged decompression are substantially more risky than dives that stay well within no-stop limits .

  • Page 5: Introduction

    The Shearwater NERD 2 is an advanced hands-free technical diving computer for open and closed circuit divers . Although we strive to make the NERD 2 easy enough to use without reading the manual, please take some time to read this manual to get the best performance from your new...

  • Page 6: Models Covered By This Manual

    The Shearwater NERD 2 also has an Open Circuit Recreational mode (OC Rec) . Operation for the NERD 2 in OC Rec mode is identical to that of the Shearwater Perdix . For detailed instructions on OC Rec mode, please see...

  • Page 7: Feature List

    Shearwater NERD 2 — User Manual FEATURE LIST Depth, time and oxygen Automatic PPO2 set-point sensor display switching (configurable) Bühlmann decompression 5 CC and 5 OC gases model with gradient factors Gases can be changed and conservatism added during a dive...

  • Page 8: Basic Operation

    BASIC OPERATION *(simulated representation of the display) The NERD 2 is mounted in front of the face . The screen image floats in view for the entire dive, showing all information needed for technical, recreational or rebreather diving . or a 25" TV, 12' away...
  • Page 9 So the NERD 2 will automatically turn-on when about 0 .9 m (3 ft) underwater when at sea level . If at higher altitude, then the NERD 2 auto-on will occur at a deeper depth . For example, when at 2000 m (6500 ft) altitude the atmospheric pressure is only about 800 mbar .
  • Page 10 > Saves the setting’s value BOTH BUTTONS When NERD 2 is off pressing MENU and SELECT at the same time will turn the NERD 2 on . No other operation requires pressing both buttons at the same time . DEPTH TIME...

  • Page 11: Mounting

    MOUNTING THE NERD 2 ON AN OPEN CIRCUIT REGULATOR The NERD 2 is designed to mount on your second stage regulator hose with the open circuit mount to ensure the eyepiece is easily viewable while diving . It does this with a removable mount that provides a solid platform and quick adjustment of the NERD 2 .
  • Page 12 Shearwater NERD 2 — User Manual STEPS FOR INSTALLING THE NERD 2 WITH THE OC MOUNT 1) Remove the collar screw form the NERD 2 mount with the hex key provided 2) Insert the NERD 2 into the retaining collar...
  • Page 13 MOUNTING THE NERD 2 ON A CLOSED CIRCUIT LOOP The NERD 2 is designed to mount on your rebreather loop with the closed circuit mount to ensure the eyepiece is easily viewable when diving . It does this with a removable mount that provides a solid platform and quick adjustment of the NERD 2 .
  • Page 14 STEPS FOR INSTALLING THE NERD 2 WITH THE CC MOUNT 1) Insert and secure mounting slide 2) Insert NERD 2 into collar and secure with screw . 3) Mate loop mount and NERD 2 assembly 4) Select a location on you rebreather mouthpiece to mount the NERD 2 .
  • Page 15 Shearwater NERD 2 — User Manual ALTERNATE MOUNTING FOR THE NERD 2 The NERD 2 incorporates mounting points that allow it to be backward compatible with some mounts designed for the original Shearwater NERD . In addition, these mounting points allow for a wide range of other mounting possibilities .

  • Page 16: The Main Screen

    Shearwater NERD 2 — User Manual THE MAIN SCREEN The main screen shows the most important information needed for technical diving . DEPTH TIME STOP TIME Top Row 220 22 130 Depth, Time & Deco Stops 1.20 1.22 1.21 Centre Row...

  • Page 17: The Top Row

    Shearwater NERD 2 — User Manual THE TOP ROW The top row shows depth and time information DEPTH TIME STOP TIME 220 22 130 Depth Imperial: In feet Metric: In meters (displays with (no decimal places). 1 decimal place up to 99.9m)
  • Page 18 Shearwater NERD 2 — User Manual Dive Time The length of the current dive in minutes. The seconds display as a bar drawn below the word “Time.” It takes 15 seconds to underline each character in the word. Does not display the seconds bar when not diving.
  • Page 19 90ft stop depth By default the NERD 2 uses a 10ft (3m) last stop depth. At this setting, you may perform the last stop at 20ft (6m) with no penalty. The only difference is that the predicted time-to-surface will be shorter than the actual TTS since off-gasing is occurring slower than expected.
  • Page 20 Shearwater NERD 2 — User Manual Surface Interval When on the surface, the STOP DEPTH and TIME are replaced by a surface interval display. Shows the hours and minutes since the end of your last dive. Above 4 days, the surface interval is displayed in days.

  • Page 21: The Center Row

    Shearwater NERD 2 — User Manual THE CENTER ROW The center row displays PPO2 . PPO2 units are absolute atmospheres (1ata = 1013mbar) . The layout varies depending on the current mode Mode Menu Setup Center Row Display Mode Setup...

  • Page 22: Center Row Configuration

    0 56 Next Edit The centre row on the NERD 2 is configured the same way as on a Shearwater Petrel . See below for a video walkthrough of how to configure the center row . Watch the video: Configurable Center Row...
  • Page 23 Shearwater NERD 2 — User Manual Center Row Options Option Description None Blank (default value) . Max Depth The maximum depth of the current or previous dive . Avg Depth The average depth of the current or previous dive .

  • Page 24: The Bottom Row

    Shearwater NERD 2 — User Manual THE BOTTOM ROW The bottom row displays the current mode, gas and decompression information. O2/HE OC 15/40 0 56 Circuit Mode The current breathing configuration . One of: OC = Open circuit SC = Semi-closed circuit...
  • Page 25 Shearwater NERD 2 — User Manual No Decompression Limit (NDL) The time remaining, in minutes, Once NDL reaches 0 (i.e. deco at the current depth until stops needed), the NDL display decompression stops will be is just wasting space. To address Yellow necessary.
  • Page 26 Shearwater NERD 2 — User Manual The bottom row is also used to show additional information. By using only the bottom row for this additional information, the critical information contained on the Top and Center Rows is always available during a dive.

  • Page 27: Info Screens

    Pressing the MENU (left) button will also return to the main screen. The info screen content is optimized for each mode. Set the NERD 2 to the mode you will be using (e.g. OC Tec) and step through the info screens to get familiar with the content.
  • Page 28 Shearwater NERD 2 — User Manual Average Depth Displays the average depth of the current dive, updated once per second. When not diving, shows the average depth of the last dive. AvgATM Average Depth in Atmospheres (AvgATM) 2.52 The average depth of the current dive, measured in absolute atmospheres (i.e.
  • Page 29 The purpose of this value is to show what PPO2 is actually being used for decompression calculations. PPO2 When three external sensors are used, the NERD 2 votes on the three measured values to decide what is the most likely true PPO2. This value shows the result of the voting.
  • Page 30 Also, this scale changes with depth, since the M-Value line also changes with depth. The video below demonstes how to interpret the tissues bar graph on a Shearwater Petrel . The NERD 2's tissue bar graph is identical . Watch the video: Tissues Demo...
  • Page 31 Shearwater NERD 2 — User Manual TISSUES 16 tissue compartments Increasing pressure Inspired inert M-Value gas pressure pressure Ambient pressure Sample Tissues Graphs TISSUES On surface (sat . with air) Note: Gas is 79% N (21% O , or Air)
  • Page 32 (now) pressure. The current pressure is only shown on the surface. The surface pressure is set when the NERD 2 is turned on. If the Altitude setting is set to SeaLvl, then surface pressure is always 1013 millibars.

  • Page 33: Compass

    Shearwater NERD 2 — User Manual COMPASS DEPTH TIME STOP TIME 22.1 1.30 1.30 1.29 The NERD 2 contains a tilt-compensated digital compass in the eyepiece. The compass indicates the direction you are looking. Compass features: 1° resolution ±5° accuracy Smooth, high-speed refresh rate...
  • Page 34 Most divers will find this a redefining your natural way of interpreting heading when prone direction. A video demonstration of compass operation on the Petrel 2 dive computer can be found below. (operation is the same for NERD 2): Watch the video: Compass Features...
  • Page 35 Shearwater NERD 2 — User Manual Marking a Heading DEPTH TIME STOP TIME 22.1 To mark a heading, when viewing the 1.30 1.30 1.29 compass press the MENU (left) button. This brings up the "Exit Mark" menu. Press the SELECT (right) button to mark the heading.
  • Page 36 This adjustment can also be used to compensate if the NERD 2 is mounted with a slight angle to your forward direction. Magnetic inclination (or magnetic dip) is how much the Earth's magnetic field points up or down.

  • Page 37: Air Integration

    Shearwater NERD 2 — User Manual AIR INTEGRATION All NERD 2 models are equipped with dual transmitter air integration capability. For complete information on how to operate the various PERDIX AI Operating Instructions manual . features of AI, see the Features •...

  • Page 38: Operating Modes

    Shearwater NERD 2 — User Manual OPERATING MODES The Mode setting allows tailoring the NERD 2 to specific types of diving. Use the correct mode to get the best experience from the NERD 2. The following modes are available: Mode...
  • Page 39 Shearwater NERD 2 — User Manual Operating Modes (continued) The following images show the main screen in each mode. Mode Name Main Screen Mode Description SAFETY STOP 1:48 Open Circuit Recreational Recreational Diving mode - Not TIME OC Rec covered by this manual. See:...
  • Page 40 Shearwater NERD 2 — User Manual Operating Modes (continued) Mode Name Main Screen Mode Description A simple bottom timer. No de- compression displays. With large depth and time in- Gauge cluding seconds. Stopwatch function plus reset- table average depth. A simple bottom timer that also shows external measured PPO2.

  • Page 41: Gauge Mode

    Shearwater NERD 2 — User Manual GAUGE MODE Gauge Mode turns the NERD 2 into a simple depth and time display (a.k.a. a bottom timer). SURFACE 2 35 Change to Gauge Mode in the System Setup Dive Setup menu. Since decompression tissues are not tracked in Gauge Mode, changing to or from Gauge Mode resets the deco tissues.

  • Page 42: Simple Oc Example Dive

    6 mpm. and a minute later when the computer comes out of dive mode, the NDL goes to 0 as well. An example dive preformed on the Shearwater Petrel can be found here: Watch the video: Air - Dive...

  • Page 43: Simple Cc Example Dive

    (21/00). Typically a PPO2 setpoint of 0.7 will be used at the surface. Once the descent has started the NERD 2 will change to dive mode. In dive mode dive time starts counting and the surface interval display changes to stop depth and time.
  • Page 44 Shearwater NERD 2 — User Manual Simple CC Dive Example (continued) It is safe to ascend to 40ft. 2 minutes must be spent at this deco stop. While ascending, the bar graph to the right of the depth shows the ascent rate.

  • Page 45: Complex Cc Dive Example

    Shearwater NERD 2 — User Manual COMPLEX CC DIVE EXAMPLE The following is a more complex rebreather dive that includes dive-planning and multi-gas OC bailout. Diluent: Trimix (10/50) Bailout gases: 10/50, 21/00, and 50/00 Max Depth: 90 meters for 20 minutes...
  • Page 46 Shearwater NERD 2 — User Manual Complex CC Dive Example (continued) Dive Phase Description NERD Display If the PPO2 sensors need calibration, fol- low the instructions from your rebreather manufacturer. On the PPO2 calibration screen, the top row displays the millivolt (mV) reading from each sensor.
  • Page 47 Shearwater NERD 2 — User Manual Complex CC Dive Example (continued) Dive Phase Description NERD 2 Display As we descend, the NDL decreases. Decreasing The TTS shows it will take 5 minutes to ascend to the surface at 10m/min (33ft/ min).
  • Page 48 Shearwater NERD 2 — User Manual Complex CC Dive Example (continued) Dive Phase Description NERD 2 Display After physically switching the BOV or mouthpiece, the computer needs to be set to BO mode for proper deco calculations. Two presses on MENU brings up the "SWITCH CC ->...

  • Page 49: Decompression And Gradient Factors

    Shearwater NERD 2 — User Manual DECOMPRESSION AND GRADIENT FACTORS The basic decompression algorithm used for the computer is Bühlmann ZHL-16C. It has been modified by the use of Gradient Factors that were developed by Erik Baker. We have used his ideas to create our own code to implement it.
  • Page 50 Shearwater NERD 2 — User Manual Graph from Erik Baker’s “Clearing Up The Confusion About Deep Stops” Pressue Graph: Gradient Factors 100% 80% 60% 40% M-value Gradient GF Lo generates first stop Linear function for gradual change in Gradient Factors...

  • Page 51: Menus

    Shearwater NERD 2 — User Manual MENUS Press MENU (left) button to step through DEPTH TIME STOP TIME 220 22 130 the menus. GasPO2 Press SELECT (right) button to execute 1.15 command or enter sub-menu. O2/HE Menus display on the bottom row.
  • Page 52 Shearwater NERD 2 — User Manual The following sections show the menu structure in various operating modes. OC TEC MENU STRUCTURE Main Screen Turn Off Surface only Select Gas Sub-Menus Dive Setup Define Gas Conserv. Dive Planner NDL Display Start Bluetooth...
  • Page 53 Shearwater NERD 2 — User Manual CLOSED CIRCUIT (INT . PPO2) MENU STRUCTURE Main Screen Turn Off Surface only Switch .7 > 1.3 only Select Gas Sub-Menus Define Gas Switch CC > BO Dive Planner Dive Setup Conserv. Edit Low SP...
  • Page 54 Shearwater NERD 2 — User Manual CLOSED CIRCUIT (EXT . PPO2) MENU STRUCTURE Main Screen Turn Off Surface only Calibrate Surface only Switch .7 > 1.3 only Sub-Menus Select Gas Define Gas Switch CC > BO Dive Planner Edit Low SP Conserv.
  • Page 55 Shearwater NERD 2 — User Manual GAUGE MENU STRUCTURE Main Screen Turn Off Surface only Start/Stop Stopwatch Reset Stopwatch Only if running Reset Avg Depth Diving only Sub-Menus Dive Setup Brightness Start Bluetooth Surface only Dive Log Display Log Delete All Logs...

  • Page 56: Turn Off

    Shearwater NERD 2 — User Manual MENU REFERENCE STOP DEPTH TIME TIME GasPO2 Turn Off TURN OFF The “Turn Off” item puts the computer to sleep. While sleeping, the screen is blank, but the tissue contents are maintained for repetitive diving. The “Turn Off” menu item will not appear during a dive on any model.

  • Page 57: Calibration

    Shearwater NERD 2 — User Manual CALIBRATION DEPTH TIME SURFACE The Calibrate menu will only appear when in CC mode with the PPO2 mode set to Ext. This menu calibrates the mV output from the oxygen sensors to PPO2. Upon selecting the calibration menu, the screen will...

  • Page 58: Single Sensor Mode

    Shearwater NERD 2 — User Manual SINGLE SENSOR MODE A single external O2 sensor may be used. To enter this mode, perform the calibration with only the middle sensor connected (sensor #2). The NERD will see that only one sensor is connected, and automatically switch to single sensor mode.

  • Page 59: Calibration Problems

    Shearwater NERD 2 — User Manual CALIBRATION PROBLEMS DEPTH TIME SURFACE One sensor displays FAIL after calibration This could indicate a bad sensor. It has failed because the FAIL mV output was not in range. The sensor could be old or damaged, and should be inspected.

  • Page 60: Switch Setpoint

    Shearwater NERD 2 — User Manual DEPTH TIME SURFACE DEPTH TIME SURFACE O2/HE Switch .7 > 1.3 CC 10/50 SWITCH SETPOINT This menu is only available under two conditions: 1. In CC mode when PPO2 is set to int (internal).

  • Page 61: Select Gas

    Shearwater NERD 2 — User Manual SELECT GAS This menu item allows you to pick a gas from the gases you have created. The selected gas will be used either as the breathing gas in open circuit mode, or the diluent in closed circuit mode.

  • Page 62: Radio Station Gases

    Shearwater NERD 2 — User Manual Radio Station Gases For computer models that support open circuit and closed circuit operation, the system maintains two sets of gases - one for open circuit and one for closed circuit. The way they operate is very similar to the way car radios work with AM and FM stations.

  • Page 63: Select Gas Menu Styles

    Shearwater NERD 2 — User Manual Adv. Config 1 White Main Color Title Color Cyan End Dive Delay 060s Bat Icon Always Gas Select Classic Change Save TIME DEPTH TIME STOP 21.4 22 21 Classic Select Gas GasPO2 2 OC On...

  • Page 64: New Style Select Gas

    Shearwater NERD 2 — User Manual TIME TIME DEPTH TIME STOP DEPTH TIME STOP TIME DEPTH TIME STOP 21.4 22 21 21.4 22 21 21.4 22 21 GasPO2 GasPO2 GasPO2 1.10 99/00 50/00 35/30 99/00 50/00 21/00 99/00 50/00 21/00...

  • Page 65: Switch To Cc/Bo

    Shearwater NERD 2 — User Manual SWITCH TO CC/BO DEPTH TIME SURFACE Depending on the current computer setting, this selection will show as .85 .86 .84 either “Switch CC > BO” or “Switch BO > CC”. Switch CC -> BO Pressing SELECT will select the displayed mode for decompression calculations.

  • Page 66: High Setpoint

    Shearwater NERD 2 — User Manual DEPTH TIME SURFACE GasPO2 Another press of MENU will increment it again. Edit High SP Next Edit DEPTH TIME SURFACE If SELECT is pushed, the currently displayed setpoint will be selected, and the display will GasPO2 return to the “Edit Low...

  • Page 67: Define Gas

    Shearwater NERD 2 — User Manual Define Gas DEPTH TIME STOP TIME The function allows you to set up 5 gases in Closed Circuit and 5 gases in Open Circuit. You GasPO2 must be in Open Circuit to edit open circuit gases, and you must be in Closed Circuit to edit closed circuit diluents.
  • Page 68 Shearwater NERD 2 — User Manual DEPTH TIME STOP TIME GasPO2 Pushing SELECT will lock in the current digit, and move on to the next digit. 2 OC On 50/00 Change Next DEPTH TIME STOP TIME Pushing SELECT on the last digit will finish editing that gas, and bring you back to the gas number.
  • Page 69 Shearwater NERD 2 — User Manual W ARNING ONLY TURN-ON GASES YOU ARE CARRYING Only turn on the gases you are actually carrying on the dive . With radio station gases, the computer has a full picture of the OC and CC gases you are carrying and can make informed predictions about decompression times .

  • Page 70: Dive Planner

    In closed-circuit (CC) mode, also calculates open-circuit (OC) bail-out (BO). Setup Uses the current gases programmed into the NERD 2, as well as the current GF low/high settings. VPM-B dive planning is available on units with the optional VPM-B unlock. Deco profile is computed for the current circuit mode (CC or OC).
  • Page 71 Shearwater NERD 2 — User Manual The Dive Planner does not provide thorough validation of the profile. For example, it does not check for nitrogen narcosis limitations, gas usage limitations, CNS percentage violations, or isobaric counter-diffusion risks due to sudden helium switches.

  • Page 72: Conservatism

    Shearwater NERD 2 — User Manual The final result screen shows the total dive time, the time spent on deco and final CNS%. Depth Time RMV PO2 CC Summary Run: 61 minutes Results Summary Screen Deco: 31 minuntes CNS: Quit Plan BO If no decompression is required, no table will be shown.

  • Page 73: Ndl Display

    Change Save the effects of following a continuous ceiling instead of stopping at stops and only moving up to the next stop when the stop has cleared. It is Shearwater's opinion that all stops should DEPTH TIME STOP TIME be honored. It seems intuitive that if you have bubbles, and you stop, you give the bubbles an opportunity to be reabsorbed.

  • Page 74: Depth

    Shearwater NERD 2 — User Manual The next option is to display the actual DEPTH TIME STOP TIME supersaturation gradient for a pure Bühlmann (99/99) profile. GasPO2 The selection is GF99. With this setting, as long NDL Display GF99 as the NDL time is 0 (you have a decompression ceiling), the gradient will be displayed instead of the NDL.
  • Page 75 Shearwater NERD 2 — User Manual The next selection is @+5. This feature was DEPTH TIME STOP TIME inspired by Dan Wible’s CCR2000 computer (Thanks Dan!). It is the time-to-surface (TTS) if GasPO2 you were to stay at the current depth for five more minutes.

  • Page 76: External Ppo2 Monitoring

    Shearwater NERD 2 — User Manual EXTERNAL PPO2 MONITORING TIME STOP DEPTH TIME The next menu item is used to turn external PPO2 monitoring on and off. By default, external monitoring is turned off and reads “Int.” for Internal fixed setpoint mode.
  • Page 77 Shearwater NERD 2 — User Manual Switching to Open Circuit bailout (BO) with External PPO2 Monitoring If you bailout to BO mode, the external PPO2 will continue to display on the main screen. However, the system PPO2 used for deco calculations will change to OC mode (i.e.

  • Page 78: Brightness

    Shearwater NERD 2 — User Manual BRIGHTNESS DEPTH TIME SURFACE GasPO2 Brightness Auto Exit Edit The display brightness has four fixed brightness settings. The fixed options are: Cave: Longest battery life. Low: Second longest battery life. Med: Best mix of battery life and readability.

  • Page 79: Dive Log Menu

    TIME SURFACE The dive log number can be edited. This is useful if you want the GasPO2 NERD 2 log numbers to match your lifetime dive count. Next Log= 0000 At the “Next Log Number” prompt, press SELECT to begin...

  • Page 80: Gaspo2

    GasPO2 Deletes All of the Logs. Delete All Logs Deleted Logs can be restored by toggling Restore Mode to on. Next Delete Lorem ipsum See the Dive Log functionality demonstrated on a Shearwater Petrel here: Watch the video: Dive Log...

  • Page 81: System Setup

    Shearwater NERD 2 — User Manual SYSTEM SETUP DEPTH TIME SURFACE GasPO2 System Setup System Setup contains configuration settings together in a convenient format for updating the configuration before a dive. System Setup cannot be accessed during a dive. However, many of the settings are also available during the dive in a single line interface.

  • Page 82: Mode Setup

    When changing to or from Gauge / PPO2 mode, the decompression tissues are cleared. This is because when in Gauge mode the NERD 2 does not know what gas you are breathing, and therefore cannot track inert gas loading. Salinity Water type (salinity) affects how the measured pressure is converted to depth.
  • Page 83 Shearwater NERD 2 — User Manual Mode Setup Mode CC/BO Salinity Salt PPO2 Mode Int. Low SP High SP Next Edit PPO2 Mode PPO2 mode is only set when CC is enabled. On the SA model this value is always Int. (internal fixed PPO2).

  • Page 84: Deco Setup

    Shearwater NERD 2 — User Manual DECO SETUP Deco Model Deco Setup May just show Bühlmann ZHL-16 with gradient factors model, or it may allow you to switch between GF and various types of VPM-B. Deco Model The choices will be available if you have unlocked VPM-B.
  • Page 85 Shearwater NERD 2 — User Manual O2 Setup O2 Setup This menu page is only available in Closed-Circuit (CC) or Semi-Closed (SC) mode when PPO2 mode is set to external Cal. FO2 0.98 Sensor Disp Giant (see Dive Setup page).
  • Page 86 Shearwater NERD 2 — User Manual Auto SP Switch Auto SP (Setpoint) Switch This menu page is only available in CC mode when PPO2 mode is set to internal (see Dive Setup page). 0.7>1.3 Auto Up Depth 070ft Auto Setpoint Switch configuration sets up the setpoint switching.
  • Page 87 Shearwater NERD 2 — User Manual Display Setup Display Setup Depth Units Feet Temp. Units Brightness Auto Altitude SeaLvl Flip Screen Next Edit Depth and temperature units can be set independently. Depth Units Temp Units Two options are available: Two options are available: Feet: Imperial units °F: Imperial units...
  • Page 88 Flip Screen Change Save Change Save If the NERD 2 measures the surface pressure to be less than 965 mbar, then the Altitude setting will be forced to "Auto" and cannot be changed. DETERMINATION OF SURFACE PRESSURE Accurate depth measurements and decompression calculations require knowing the ambient atmospheric pressure at the surface .
  • Page 89 Shearwater NERD 2 — User Manual Flip Screen This function displays the contents of the screen upside down. The Flip Screen option is useful if helmet or mask mounting the NERD 2...

  • Page 90: Compass Setup

    Shearwater NERD 2 — User Manual COMPASS SETUP Compass Compass View Calibrate True North Next Edit Compass View The Compass View setting can be set to the following: Off: The compass is disabled. 60°, 90°, or 120°: Sets the range of the compass dial that is visible on the main screen.
  • Page 91 Calibration of the compass may be needed if the accuracy drifts over time or if a permanent magnet or ferromagnetic metal (e.g. Enable iron or nickel) object is mounted very close to the NERD 2. To be Calibrate calibrated out, such an object must be mounted with the NERD 2 Adjust True North so that it moves along with the NERD 2.

  • Page 92: System Setup

    Defaults’. This will reset all user changed Time 12:28PM options to factory settings and clear the tissues Unlock on the NERD 2. ‘Reset to Defaults’ cannot be Reset to Defaults reversed. Next Reset Note: This will not delete dive logs, or reset dive...

  • Page 93: Advanced Configuration 1

    Shearwater NERD 2 — User Manual ADVANCED CONFIGURATION 1 Advanced configuration contains items that will be used Advanced Config infrequently and can be ignored by most users. They provide more detailed configurations. Enter Adv. Config Reset Adv. Config The first screen allows you to enter the advanced configuration...

  • Page 94: Advanced Configuration 2

    Shearwater NERD 2 — User Manual ADVANCED CONFIGURATION 2 This section allows changing of PPO2 limits. WARNING Do not change these values unless you understand the effect . All values are in absolute atmospheres [ata] of pressure (1 ata = 1.013 Bar) Adv.

  • Page 95: Starting Bluetooth

    It is important to keep the firmware on your dive computer up to date. In addition to new features and improvments, firmware updates address important bug fixes. There are two ways to update the firmware on your NERD 2: With Shearwater Desktop 2) With Shearwater Cloud Mobile Upgrading the firmware resets decompression tissue loading .
  • Page 96 The NERD 2 screen will give percentile updates of receiving the firmware, and then the Personal Computer will read “Firmware successfully sent to the computer” on completion.   After receiving the new firmware, the NERD 2 will reset and display a message stating either firmware update success or failure.
  • Page 97 The NERD 2 screen will give percentile updates while receiving the firmware, and the phone will read “Firmware successfully sent to the computer” upon completion.   After receiving the new firmware, the NERD 2 will reset and display a message stating either firmware update success or failure.

  • Page 98: Dive Log Download

    Shearwater NERD 2 — User Manual DIVE LOG DOWNLOAD DIVE LOG DOWNLOADING WITH SHEARWATER DESKTOP In Shearwater Desktop, go to Dive Computer Download Dive Log The Download Dive Log window should pop up. Start Bluetooth on your NERD 2...
  • Page 99 Shearwater Desktop will transfer the dives to your computer. The first time you download dives from your NERD 2, you will be asked to give the NERD 2 a name. If you have multiple Shearwater dive computers, you will be...
  • Page 100 Shearwater NERD 2 — User Manual DIVE LOG DOWNLOADING WITH SHEARWATER CLOUD MOBILE In Shearwater Cloud Mobile, connect to the dive computer, and select download dives. Once connected it will download a list of available dive logs and you will see a screen like this.
  • Page 101 CHARGING ATTACH THE NERD 2 CHARGING CLIP Align the charging pins on the clip with the pins on the NERD 2 using the clip guides atop the charging clip. Connect the clip by applying pressure to the bottom of the clip until it snaps into place.

  • Page 102: Behavior On Dead Battery

    Shearwater NERD 2 — User Manual CHARGING TIME The NERD 2 can be charged with any USB wall power adaptor or with a computer. Charging time is approximately 3-4 hours. BEHAVIOR ON DEAD BATTERY We recommend that you never allow the battery fully discharge to prevent damage .
  • Page 103 Shearwater NERD 2 — User Manual For quick dead-battery intervals, the un-powered time interval is not significant. However, if the battery dies shortly after a dive and remains dead for a long period, then residual tissue loading will remain when the battery is charged again. If you have not been diving for more than 4 days, it is safe to reset the tissues to their default levels (System Setup->Reset to Defaults->Tissues Only).
  • Page 104 Shearwater NERD 2 — User Manual LIMITATIONS OF ALARMS All alarm systems share common weaknesses . They can alarm when no error condition exists (false positive) . Or they can fail to alarm when a real error condition occurs (false negative) .
  • Page 105 Shearwater NERD 2 — User Manual ALERT DISPLAYS The system has several displays that alert to warnings, errors, and information alerts. Each alert will remain in the bottom row of the main screen until it is dismissed by pressing the SELECT (right) button.
  • Page 106 Shearwater NERD 2 — User Manual Alert Description Solution Low Battery Int. The internal battery is low. Recharge the battery. Switch to a gas with a lower Central Nervous System (CNS) PPO2 or ascend shallower High CNS toxicity clock high exceeded (decompression ceiling allow- 90%.
  • Page 107 Shearwater NERD 2 — User Manual ALERT DISPLAY SCREENS These sample screens correspond to the errors listed above. Each of the alerts will display the message until dismissed. The error is dismissed by pressing SELECT. DEPTH TIME STOP TIME GasPO2...
  • Page 108 Shearwater NERD 2 — User Manual Ascent DEPTH TIME STOP TIME This alarm is a notification that there has either been a very fast ascent for a short period of time, or that there GasPO2 1.12 has been an ascent of more than 66 fpm / 20 mpm maintained for over a minute.

  • Page 109: Storage And Maintenance

    Do not wash under high pressure jets of water as it may cause damage to the depth sensor. Store the NERD 2 dive computer out of direct sunlight in a cool, dry and dust free environment. Avoid continuous exposure to direct ultra-violet radiation and radiant heat.

  • Page 110: Specifications

    Shearwater NERD 2 — User Manual SPECIFICATIONS Specification Stand Alone (SA) Fischer DiveCAN DiveCAN (FC) Controller Monitor (DCC) (DCM) Operating Modes OC Tec OC Tec CC/BO OC Tec OC Rec OC Rec OC Rec CC/BO (int. PPO2) CC/BO CC/BO Gauge...
  • Page 111 Shearwater NERD 2 — User Manual FCC WARNING a) USA-Federal Communications Commission (FCC) This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation.

  • Page 112: Contact

    Shearwater NERD 2 — User Manual CONTACT Shearwater Research Inc . EU Service Center Headquarters Narked at 90 Ltd 13155 Delf Place, Unit 250 15 Bentley Court, Richmond, BC Paterson Rd, V6V 2A2 Wellingborough, Tel: +1.604.669.9958 Northants, UK info@shearwater.com NN8 4BQ Tel: +44.1933.681255...
  • Page 113 Shearwater NERD 2 — User Manual End of Manual...

This manual is also suitable for:

Nerd 2 seriesNerd 2 saNerd 2 fcNerd 2 dccNerd 2 dcm

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